The weights of extra large eggs have a normal distribution with a mean of one ounce and a standard deviation of 0.1 ounces. The probability that a dozen eggs weighs more than 13 ounces is closest to...?

1 answer

you might want to look at my answer to Belinda, 5 posts back

Her problem and yours are the same style

For your question you have to divide 13 by 12 to get the weight of one egg.