Answer:
As you know, a year has around 365 + 1/4 days.
This means that in two years, we have:
365 + 356 + 1/4 + 1/4 = 730 + 1/2
and so on.
adding this up, when we have 4 years we have a full day extra, this is:
1460 + 1
When we divide 1461 by 4, we have 365 with a surpass of 1.
The rule used to keep the calendar in sync with this extra day is adding an extra day to each fourth year.
So each fourth year, we have an extra day in Februray (the Februray 29th), this is called a bisiest year.
The "math rule" used to know if a year is leap or not is:
if a year is not divisible by 4, then it is a common year
else if the year is not divisible by 100 then it is a leap year,
else if the year is not divisible by 400, then it is a common year
if not, the year is a leap year.
Where "year" represents the number of the year.
Calculate the product of 8/15, 6/5, and 1/3.
B. 16:15
D. 16/75
A. 48
0115
Answer:
16/75, D
Step-by-step explanation:
6/5*1/3. We can cross simplify to make it 2/5*1/1. That is 2/5. Then, 2/5*8/15 is 16/75 which is answer choice D.
Please help! I'm stuck on this one :(
Answer:
[900, 1300]
Step-by-step explanation:
According to the empirical rule, 95% is within ±2 standard deviations.
1100 − 2(100) = 900
1100 + 2(100) = 1300
What is the value of x if f(x) = 76
Answer:
The roots (zeros) are the x values where the graph intersects the x-axis. To find the roots (zeros), replace f(x) with 0 and solve for x
No solution
One of the methods forensic investigators use for estimating the age at death of a human, or the age of a living individual (for example for legal reasons or to verify identity) is based on measurement of the biochemical changes in amino acids within the teeth or bones. As bones and teeth age the ratio (R/L) of two amino acids, denoted simply as R and L, increases. The biochemical changes that occur over time in these amino acids follow an exponential law. The age t, in years, can be estimated from (R/L) using the equation t = b0 + b1*LN((1+R/L)/(1-R/L))^(), where LN denotes the natural logarithm (logarithm base e). This Excel file has data on the ratio (R/L) from the teeth of human subjects of known age.
1. Use the data to find the least squares intercept b0 and slope b1 in the equation t = b0 + b1*LN((1+R/L)/(1-R/L))^(). intercept b0 slope b1
2. While tending to his flower garden, Sherlock Holmes discovers a body buried in his backyard. Forensic analysis yields the value 0.045 for the ratio (R/L). Use the least squares equation to estimate the age of Sherlock Holmes' surprise garden visitor. years
3. Calculate a 95% prediction interval for the age at death of Sherlock Holmes' surprise garden visitor. lower bound upper bound
4. Several years ago a man in Sherlock Holmes's neighborhood mysteriously disappeared. At the time of the disappearance the man was 35 years old. Do you think that this is the body of that man? No Yes
Answer: While tending to his flower garden, Sherlock Holmes discovers a body buried in his backyard. Forensic analysis yields the value 0.045 for the ratio (R/L). Use the least squares equation to estimate the age of Sherlock Holmes' surprise garden visitor. years
Step-by-step explanation:
1.x2+3x+3=0
2.x2-2x-3=0
3.x2-6x+9=0
4.-x2+3=0
Step-by-step explanation:
the two A's in the buttom is correct
What must be a factor of the polynomial function f(x) graft on the coordinate plane below
X - 6
x - 3
x + 1
x +6
Answer:
Option D.
Step-by-step explanation:
The given graph represents the function f(x).
If graph of a function f(x) intersect x axis at x=c, then (x-c) is a factor of f(x).
From the given graph it is clear that the graph of f(x) intersect x axis at x=-6,-3,0. It means factors of given function are
[tex](x-(-6))=(x+6)[/tex]
[tex](x-(-3))=(x+3)[/tex]
[tex](x-0)=x[/tex]
It means (x+6), (x+3) and x are factors of given function.
Therefore, option D is correct.
Answer:
The answer is (x+6)
Step-by-step explanation:
Just took the test
Hope this helps
In a large class in statistics, the final examination grades have a mean of 67.4 and a standard deviation of 12. Assuming that the distribution of these grades is normal, the number of passes in a class of 180 is:_________ (if you get a number with decimals points, round up to the next whole number)
Answer:
The number of passes in a class of 180 is 75.
Step-by-step explanation:
The problem does not state, so I will suppose the passing grade is 70.
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this question:
[tex]\mu = 67.4, \sigma = 12[/tex]
Proportion of students who passed:
This is 1 subtracted by the pvalue of Z when X = 70. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{70 - 67.4}{12}[/tex]
[tex]Z = 0.22[/tex]
[tex]Z = 0.22[/tex] has a pvalue of 0.5871.
1 - 0.5871 = 0.4129
Out of 180:
0.4129*180 = 74.32
Rounding up
The number of passes in a class of 180 is 75.
Given the following exponential function, identify whether the change represents
growth or decay, and determine the percentage rate of increase or decrease.
y = 940(1.89)
Answer: The change represents growth with 89% of growth rate.
Step-by-step explanation:
The exponential function is given by :-
[tex]f(x)= Ab^x[/tex]... (i)
Where , A = initial value , b= multiplicative factor and x= time period
We call 'b' growth factor when b>1, we can write b= 1+r , where r is the rate of growth.We call 'b' decay factor when b<1 , we can write b= 1-r , where r is the rate of decay.The given function : [tex]y = 940(1.89)^x[/tex].
By comparing this to (i) , we get
b= 1.89 > 1 , thus it represent the growth.
Also,
[tex]b= 1+r\Rightarrow\ 1.89 = 1+r\\\\\Rightarrow\ r=1.89-1=0.89[/tex]
i.e. Percentage rate of growth = 0.89 x 100 = 89%.
the table shows miles driven by a car and the gallons of gas used to drive those miles. how many miles did the car travel on a gallon of gas?
Answer:
May we see the graph?
Step-by-step explanation:
Which angle is in standard position?
On a coordinate plane, 2 rays form an angle and both rays are not on the y- or x-axis.
On a coordinate plane, 2 rays form an angle and both rays are not on the y- or x-axis.
On a coordinate plane, 2 rays form an angle. One ray sits on the x-axis.
On a coordinate plane, 2 rays form an angle and both rays are not on the y- or x-axis.
Mark this and return
Answer:
(C)On a coordinate plane, 2 rays form an angle. One ray sits on the x-axis.
Step-by-step explanation:
An angle is stated in the standard position with respect to the x-axis.
Therefore, for an angle to be in standard position, one of its rays must be on the x-axis.
From the given options, only Option C has a ray on the x-axis and therefore is the angle that is in standard position.
Answer:
The answer to this question is C) (the third graph)
Answers to the entire test are
1. A) Quadrant 1
2. B) –270° and 90°
3. D) 126° + (720n)°, for any integer n
4. A) –90° and 630°
5. A) (the first graph)
6. D) n = 6
7. C) x = y + 360 n, for any positive integer n
8. B) 10°
9. C) (the third graph)
10. C) 495°
Step-by-step explanation:
Just took it. Edg 2021. Hope this helps :) (smiley's name is George, George says hi)
Giraffes have excellent vision. Refer to the African Zoology (Oct. 2013) study of a giraffe’s eyesight. Recall that the researchers measured the eye mass for a sample of 27 giraffes native to Zimbabwe, Africa, and found x = 53.4 grams and s = 8.6 grams. Suppose the objective is to sample enough giraffes in order to obtain an estimate of the mean eye mass to within 3 grams of its true value with a 99% confidence interval.A. Identify the cofidence coefficient for this study. B. Identify the desired sampling error for this study. C. Fnd the sample size required to obtain the desired estimate of the true mean.
Answer:
(a) The confidence coefficient is 2.779.
(b) The desired sampling error for this study is the margin of error, ±3.
(c) The sample size required to obtain the desired estimate of the true mean is 55.
Step-by-step explanation:
The information provided is:
[tex]\bar x=53.4\ \text{grams}\\s=8.6\ \text{grams}\\n=27\\\text{Confidence Level} = 99\%[/tex]
(a)
As the sample size is n = 27 < 30 and the population standard deviation is not provided a t-interval would be used to estimate the true mean.
So, the confidence coefficient for the 99% confidence interval for true mean is:
[tex]t_{\alpha/2, (n-1)}=t_{0.01/2, (27-1)}=t_{0.005, 26}=2.779[/tex]
*Use the t-table.
Thus, the confidence coefficient is 2.779.
(b)
The error caused due to incorrect sample selection, i.e. a sample that is not a true representative of the population is known as the sampling error.
In this case the sampling error is known as the margin of error of the confidence interval.
The margin of error is:
MOE = 3 grams
Thus, the desired sampling error for this study is the margin of error, ±3.
(c)
Assume that the ample size required to obtain the desired estimate of the true mean is quite large, such that the sampling distribution of sample mean follows a normal distribution according to the central limit theorem.
Then the margin of error for a z-interval for mean is:
[tex]\text{MOE}=z_{\alpha/2}\times \frac{s}{\sqrt{n}}[/tex]
MOE = 3 grams
The critical value of z for 99% confidence level is:
[tex]z_{\alpha/2}=z_{0.01/2}=z_{0.005}=2.58[/tex]
*Use a z-table.
Compute the sample size as follows:
[tex]\text{MOE}=z_{\alpha/2}\times \frac{s}{\sqrt{n}}[/tex]
[tex]n=[\frac{z_{\alpha/2}\times s}{MOE}]^{2}[/tex]
[tex]=[\frac{2.58\times 8.6}{3}]^{2}\\\\=54.700816\\\\\approx 55[/tex]
Thus, the sample size required to obtain the desired estimate of the true mean is 55.
Which of the following is a property of translations that is not also a property of other types of rigid motions? (1) they map line segments to other line segments of equal length (2) they map angles to other angles of the same size (3) they map lines to parallel lines (4) they map lines to perpendicular lines
Answer:
3 I think it's 3. sorry if I'm wrong
The correct answer is (3) they map lines to parallel lines
Transformation is the movement of a point from the initial location to a new location. Types of transformation is rotation, reflection, translation and dilation.
Translation is the movement of a point up, down, left or right in the coordinate plane.
Translation is a rigid transformation, that is, it preserves the size and shape of the figure. Reflection and rotation are also rigid transformation.
Translation maps lines to parallel lines whereas rotation does not since it changes the direction of the line.
Find out more at: https://brainly.com/question/11707700
A submarine is positioned at 300 feet below sea level. A bird is flying 100 foot above sea
level. How many feet above the submarine is the bird?
-300-200-1000
100 200 300
Answer:
h = 400 ft
The bird is 400 ft above the submarine
Step-by-step explanation:
Given;
The submarine is 300 feet below sea level
Vertical distance between submarine and sea level h1 = 300 feet
The bird is flying at 100 feet above sea level
Vertical distance between the sea level and the bird h2 = 100 feet
The total vertical distance between the bird and the submarine is the sum of the vertical distance between submarine and sea level and the vertical distance between the sea level and the bird.
h = h1 + h2
h = 300 ft + 100 ft
h = 400 ft
The bird is 400 ft above the submarine
Answer:
The bird is 400 ft above the submarine
Step-by-step explanation:
The circle above has an area of 144 pi cm^2. What is the area of the blue sector? Use 3.14 for pi.
Answer:
150.72 cm^2
Step-by-step explanation:
The blue area has an angle of 120 degrees, and 120/360 = 1/3, which shows that the blue area is 1/3 of the circle. In that case, the blue area is just 144pi/3. That simplifies to 48 pi.
48*3.14 = 150.72
Triangle ABC was dilated and translated to form similar triangle A'B'C'.
On a coordinate plane, 2 triangles are shown. Triangle A B C has points (0, 2), (2, 2), and (2, 0). Triangle A prime B prime C prime has points (negative 4, negative 1), (1, negative 1), and (1, negative 6).
What is the scale factor of the dilation?
One-fifth
Two-fifths
Five-halves
5
Answer:
Dilation is done by the scale factor of Five-halves.
Step-by-step explanation:
Please refer to the image attached,
The graph clearly shows the triangles [tex]\triangle[/tex]ABC and [tex]\triangle[/tex]A'B'C'.
Let us calculate the sides of triangles first then we will be able to find scale factor of dilation.
Using the distance formula:
Distance between 2 points [tex]P (x_1,y_1) \text{ and } Q (x_2,y_2)[/tex] is given by formula:
PQ = [tex]\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}[/tex]
Side AB is along x-axis, side AB =
[tex]\sqrt{(2-0)^2+(2-2)^2}\\\Rightarrow \sqrt{4}\\\Rightarrow 2\ units[/tex]
Similarly side, BC = 2 units
Now, in [tex]\triangle[/tex]A'B'C', A'B' can be calculated by distance formula:
[tex]\sqrt{(1+4)^2+(-1- (-1))^2}\\\Rightarrow \sqrt{25}\\\Rightarrow 5\ units[/tex]
B'C' = 5 units
The ratio of sides:
AB : A'B' = 2:5
[tex]\Rightarrow \dfrac{AB}{A'B'} = \dfrac{2}{5}\\\Rightarrow A'B' = \dfrac{5}{2} AB[/tex]
So, scaling factor is [tex]\dfrac{5}{2}[/tex] or 2.5.
OR
Scaling factor is Five-halves.
Answer:
The answer is C on Edge.
Step-by-step explanation:
The table shows the weekly income of 20 randomly selected full time students. If the
Answer: is that the full question?
Step-by-step explanation:
Please help
Blake is going to invest in an account paying an interest rate of 1.5% compounded quarterly. How much would Blake need to invest, to the nearest dollar, for the value of the account to reach $910 in 10 years?
Answer:
A, of money in the account after 3 years subject to interest ... If you deposit P dollars at rate r, in decimal form, subject to compound interest paid
Step-by-step explanation:
If x^6=20 and w^10=20, what is x^12 w^-10?
Answer:
[tex]x^{12} =400[/tex]
[tex]w^{-10} =\frac{1}{20}[/tex]
Step-by-step explanation:
[tex]x^{6} =20[/tex]
[tex]x^{12} =(x^{6} )^{2} =20^{2} =400[/tex]
[tex]w^{10} =20[/tex]
[tex]w^{-10} =\frac{1}{w^{10} } =\frac{1}{20}[/tex]
[tex]x^{12} *w^{-10} =400*\frac{1}{20} =20[/tex]
Given a regular octagon, in how many ways can we color one diagonal red and another diagonal blue so that the two colored diagonals cross (in the interior)? Consider rotations and reflections distinct.
Answer:
Rotation = 1.
Reflection = 5 or 4.
Step-by-step explanation:
A regular octagon is the octagon that has eight, 8 sides and all these eight sides are equal.
So, if we are going to consider rotation and reflection distinct in order to color one diagonal red and another diagonal blue so that the two colored diagonals cross (in the interior) we can do that by following the steps Below;
=> Make sure that the first diagonal with the red color is drawn first.
=> to another make fixing to another end.
=> Determine the possibilities.
The numbers of times can be gotten by using Burnside Lemma which gives Rotation = 1 And Reflection = 5 or 4.
Find the volume of a juice box that is 3 inches by 1/12 in by 4 inches
Answer:
The volume of the box is [tex]1 in^{3}[/tex]Step-by-step explanation:
This problem is on the mensuration of solid shapes, a box/cube.
Given data
[tex]Length l = 3in\\\\Width w= \frac{1}{12}in \\\\Height h = 4in[/tex]
we know that the expression for the volume of a cube is
[tex]volume= l*w*h\\\\substituting \\\\volume= 3* \frac{1}{12}* 4\\ volume= \frac{12}{12} = 1 in^{3}[/tex]
What is the total surface area of the square pyramid below?
14 cm
10 cm
10 cm
Answers:
100 cm
200 cm
250 cm
Answer: A = 93.8 cm so if you round up it's about 100 cm
Step-by-step explanation:
Area means you have to multiply all measurements by each other in any order of course because it doesn't matter in this case.
14 * 10 * 10 = 1400
Now you can/should divide the answer which is (1400) by how many measurements you have times the sides it has, sides - which is 5 , measurements - which is 3, so it would look like this:
1400 / 15 = 93.8
A wire 18cm long is cut into 2 pieces. the longer piece is 2 cm longer than the shorter piece. Find the lenght of the shorter piece
Answer:
8cm
Step-by-step explanation:
If the pieces are 8cm and 10cm they will still add up to 18cm but the longer piece is 2cm longer so both conditions are satisfied.
Coaching companies claim that their courses can raise the SAT scores of high school students. But students who retake the SAT without paying for coaching also usually raise their scores. A random sample of students who took the SAT twice found 427 who were coached and 2733 who were uncoached. Starting with their verbal scores on the first and second tries, we have these summary statistics: Try 1 Try 2 Gain n \overline x s \overline x s \overline x sCoached 427 500 92 529 97 29 59Uncoached 2733 506 101 527 101 21 52Use Table C to estimate a 90% confidence interval for the mean gain of all students who are coached.toat 90% confidence.Now test the hypothesis that the score gain for coached students is greater than the score gain for uncoached students. Let \mu_1 be the score gain for all coached students. Let \mu_2 be the score gain for uncoached students.(a) Give the alternative hypothesis: \mu_1 - \mu_20.(b) Give the t test statistic:(c) Give the appropriate critical value for \alpha =5%: .
Answer:
Step-by-step explanation:
The question is incomplete. The complete question is
Coaching companies claim that their courses can raise the SAT scores of high school students. But students who retake the SAT without paying for coaching also usually raise their scores. A random sample of students who took the SAT twice found 427 who were coached and 2733 who were uncoached. Starting with their verbal scores on the first and second tries, we have these summary statistics:
Try 1 Try 2 Gain
n x s x s x s
Coached 427 500 92 529 97 29 59
Uncoached 2733 506 101 527 101 21 52
Use Table C to estimate a 90% confidence interval for the mean gain of all students who are coached.
at 90% confidence.
Now test the hypothesis that the score gain for coached students is greater than the score gain for uncoached students. Let μ1 be the score gain for all coached students. Let μ2 be the score gain for uncoached students.
(a) Give the alternative hypothesis:
μ1 - μ2.
(b) Give the t test statistic:
(c) Give the appropriate critical value for \alpha =5%:
Solution:
The formula for determining the confidence interval for the difference of two population means is expressed as
Confidence interval = (x1 - x2) ± z√(s²/n1 + s2²/n2)
Where
x1 = sample mean score gain for all coached students
x2 = sample mean score gain for all uncoached students
s1 = sample standard deviation score gain of coached students
s2 = sample standard deviation score gain of uncoached students
For a 90% confidence interval, the z score is 1.645
From the information given,
x1 = 29
s1 = 59
n1 = 427
x2 = 21
s2 = 52
n2 = 2733
x1 - x2 = 29 - 21 = 8
z√(s1²/n1 + s2²/n2) = 1.645√(59²/427 + 52²/2733) = 4.97
90% Confidence interval = 8 ± 4.97
a) The population standard deviations are not known. it is a two-tailed test. The random variable is μ1 - μ2 = difference in the score gain for coached and uncoached students.
We would set up the hypothesis.
The null hypothesis is
H0 : μ1 = μ2 H0 : μ1 - μ2 = 0
The alternative hypothesis is
H1 : μ1 > μ2 H1 : μ1 - μ2 > 0
This is a right tailed test.
b) Since sample standard deviation is known, we would determine the test statistic by using the t test. The formula is
(x1 - x2)/√(s1²/n1 + s2²/n2)
t = (29 - 21)/√(59²/427 + 52²/2733)
t = 2.65
The formula for determining the degree of freedom is
df = [s1²/n1 + s2²/n2]²/(1/n1 - 1)(s1²/n1)² + (1/n2 - 1)(s2²/n2)²
df = [59²/427 + 52²/2733]²/[(1/427 - 1)(59²/427)² + (1/2733 - 1)(52²/2733)²] = 9.14/0.1564
df = 58
c) from the t distribution table, the critical value is 1.67
In order to reject the null hypothesis, the test statistic must be smaller than - 1.67 or greater than 1.67
Since - 2.65 < - 1.67 and 2.65 < 1.67, we would reject the null hypothesis.
Therefore, at 5% significance level, we can conclude that the score gain for coached students is greater than the score gain for uncoached students.
Which of the following graphs Represents the equation above -3x+ 2 y=
LA=
Round your answer to the nearest hundredth.
A
2
5
B
Answer:
I'm not so clear with the question but I hope this helps
Need helppppp asapppp
The answer is C. 65........
Answer:
25
Step-by-step explanation:
The angle of an arc is the same as the central angle. MarcCD is the same as the central angle COD which is given as 130o.
That means there are 50 degrees left for COA and DOA and because the chord and the diameter are equal, COA = DOA
That means that COA is 1/2 what is left over from 180 when 130 is subtracted from it.
1/2 * 50 = 25
The answer is A 25.
How much of other chemicals must be evaporated from 400 grams of a hand sanitizer that is 24% alcohol to strengthen it to a hand sanitizer that is 30% alcohol? Correct your answer to the nearest whole number
Answer:
Mass of other chemicals to be evaporated is 24 grams.
Step-by-step explanation:
The initial mass of the hand sanitizer = 400 grams, and has an alcohol content of 24%.
mass of its alcohol content = [tex]\frac{24}{100}[/tex] × 400
= 96 grams
mass of non-alcoholic content = 400 - 96
= 304 grams
If the percentage of alcohol is increased to 30%, then;
mass of its alcohol content = [tex]\frac{30}{100}[/tex] × 400
= 120 grams
The mass of other chemicals to be evaporated = 120 - 90
= 24 grams
Plz help fast!!! will give brainiest to first correct answer For which distributions is the median the best measure of center? Select each correct answer.
Answer:
The top left picture and top right picture
Step-by-step explanation:
(−98)+(−97)+(−96) + ⋯ +(−1)+0+1+2+ ⋯ +98+99+100
Answer:
199
Step-by-step explanation:
All of the terms of the sum cancel except the last two.
The total is 199.
round off the number 0.007326 correct to 3 significant figures 3 decimal places
Answer:0.007
Step-by-step explanation: