Answer:
0.9256
Step-by-step explanation:
Given that a convenience store owner claims that 55% of the people buying from her store, on a certain day of the week, buy coffee during their visit
Let X be the number of customers who buy from her store, on a certain day of the week, buy coffee during their visit
X is Binomial (35, 0.55)
since each customer is independent of the other and there are two outcomes.
By approximation to normal we find that both np and nq are >5.
So X can be approximated to normal with mean = np = 19.25
and std dev =
Required probability = prob that fewer than 24 customers in the sample buy coffee during their visit on that certain day of the week
= (after effecting continuity correction)
= 0.9256