Question

a study of the accuracy of fast food drive through orders restaurant A had 251 accurate orders and 69 that were not accurate construuct a 95% confidence interval estimate of the percentage of orders that are not accurat

Answer 1

Interval find variance

Varriance v = √

Use formula

Interval = t • mean / √ n. ( n is number of measures)

mean =

number of measures = 251 + 69 = 320

Now find standard deviation d = mean/ √n

d= 69/251 /√ 320 = 0.27/18 = 0.015

Then area between