The equation for the circle below is x2 + y2 = 16. What is the length of the
circle's radius?

e) 4

Step-by-step explanation:

This is the form of a circle. Use this form to determine the center and radius of the circle.

(x−h)^2+(y−k)^2=r^2

r=4

h=0

k=0

a; x = 0.5

step-by-step explanation:

-10x = -5

x = 0.5

irst, find the z score of a score of 80. this is given by the formula z = (x-u)/o, where x is the score, u is the mean, and o is the standard deviation. this gives

z = (80-78)/12 = 1/6 = .1667

now, find what percentile a z score of 1/6 correlates to in the normal distribution.

a z score of 1/6 = .1667 is equivalent to the 56.36th percentile of the distribution. so the probability a score is over this is 1-.5636 = .4364

the mean of a sample mean is equal to the original mean. however, the standard deviation of a sample mean is equal to the original standard deviation divided by the square root of n (sample size). so the new standard deviation is 12/sqrt(16) = 3.

the new z score is 80-78/3 = 2/3 = .667. this is equivalent to the 74.86th percentile. so the probability that the mean will be greater than this score is 1-.7486 = .2514.