A bakery owner wants to ensure they make enough cookies each day to meet the demand from customers. On average, they sell 92 cookies a day with a standard deviation of 9. The baker makes 70 cookies each day. Using a calculator or a spreadsheet program, find the probability that the baker made enough cookies (no more than 70 cookies sold that day). Round the answer to the nearest tenth of a percent.(1 point)
The probability that 70 cookies were enough for that day’s sales is
a
%.
The probability can be calculated using the z-score formula:
z = (X - μ) / σ
where:
X = number of cookies made by the baker (70)
μ = average number of cookies sold per day (92)
σ = standard deviation (9)
Calculating the z-score:
z = (70 - 92) / 9
z = -22 / 9
z = -2.44
Next, we need to find the probability corresponding to a z-score of -2.44. This can be found using a standard normal distribution table or a calculator. The probability of a z-score of -2.44 is approximately 1.3%.
Therefore, the probability that the baker made enough cookies (no more than 70 cookies sold that day) is approximately 1.3%.