Question

assume that the number of cappucimos a starbucks store sells each day is normally distributed with mean of 298 and a standard deviation of 16. what is the particular day the starbucks store sells atleast 322 cappuccinos? (put 4 digits after the 0 for your final result such as 0.0000)

Answer 1

Let X be the number of cappucimos a starbucks store sells each day.

X~Normal(mean=µ=298,standard deviation=ơ=16)

We are required to find  the particular day the starbucks store sells atleast 322 cappuccinos i.e the probability that X is atleast 322 i.e X ≥322.

Hence, we need to compute

P(X ≥322)

=1- P(X<322)

=1- P((X-µ)/ơ < (322-µ)/ơ)

= 1-P((X-298)/16 < (322-298)/16)

=1-P(Z<1.5) [Z=(X-µ)/ơ]

=1-0.9332 [From normal table]

=0.0668

Ans: 0.0668