What is the average rate of change of the function f(x)=20(14)xf(x)=20(14)x from x = 1 to x = 2? enter your answer, as a decimal, in the box. do not round your answer.

Average rate of change(A(x)) of f(x) over a interval [a,b] is given by:

Given the function:

We have to find the average rate of change from x = 1 to x= 2

At x = 1

then;

At x = 2

then;

Substitute these in above formula we have;

⇒

therefore, average rate of change of the function f(x) from x = 1 to x = 2 is, -3.75

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.