Sat scores of students at an ivy league college are distributed with a standard deviation of 250 points. two statistics students, raina and luke, want to estimate the average sat score of students at this college as part of a class project. they want their margin of error to be no more than 25 points.(a) raina wants to use a 90% condence interval. how large a sample should she collect? raina should sample at least people.

The sample size should be 273 students

Step-by-step explanation:

Here Raina wants to use 90% interval then

ME = z. SE

SE = s d/√n at end

ME/z   = s d/√n

n={z.sd/ME)²

Z = 1.65    =>due to  90%confidence interval

ME= 24

sd=250

putting these value in the question we get 273 students

56.6

step-by-step explanation:

the ratio of the perimeters is equal to the scale.

the ratio of the areas is equal to the square of the scale.

34 / 20 = k

a / 19.6 = k²

substituting:

a / 19.6 = (34 / 20)²

a = 19.6 (34 / 20)²

a ≈ 56.6

if the probability is 1/12, 75 people will receive a $25 gift card

step-by-step explanation: