Can someone check my answer please

A can of Pepsi is supposed to contain, on the average, 12 ounces of soda with a standard deviation of 0.3 ounces. Suspecting fraud, you take a random sample of 40 cans and measure the amount of Pepsi in each. Your measurements show that the 40 cans had a mean of 11.9 ounces. What is the probability of a random sample of 40 cans having a mean of 11.9 ounces of soda or less?

0.3707 or 37.1%

Question

Can someone check my answer please

A can of Pepsi is supposed to contain, on the average, 12 ounces of soda with a standard deviation of 0.3 ounces. Suspecting fraud, you take a random sample of 40 cans and measure the amount of Pepsi in each. Your measurements show that the 40 cans had a mean of 11.9 ounces. What is the probability of a random sample of 40 cans having a mean of 11.9 ounces of soda or less?

0.3707 or 37.1%

phi · Answer

see https://en.wikipedia.org/wiki/Standard_deviation#Standard_deviation_of_the_mean_.28SDOM.29 You compute the mean of 40 cans of soda. The mean will have a std dev of 0.3/sqr(40)= 0.047 ounces if the true mean were 12.0, 11.9 is 0.1 ounce or 0.1/0.047 std dev below, i.e. 2.1 std dev below the mean. You will get a very low probability.

anonymous · Answer

ok thank you