Answer:
(a)P(x>85.55)=0.02275
(b)
Step-by-step explanation:
We are given that
Average sales for an online textbook distributor per customer per purchase
,
$67.63
Standard deviation of the amount spent on textbooks,
$8.96
(a) We have to find probability for a randomly selected customer spent more than $85.55 per purchase.

=
=
=
P(x>85.55)=0.02275
(b)We have to find probability for a randomly selected customer spent less than $76.59 per purchase



It is 45 because angle EBC is congruent to CDE (x) because of a rule called alternate angles. so x= 45°
64 - 9 = 55 \sqrt{55} = 7.4161984871
7.4161984871/2 ≈3.7
Answer: X=7
hope that will help!
Step-by-step explanation: