Normal distribution w/ mean and standard deviation

Hey i have this question which i have answered, my answer shows 9 eggs but the books answer says 10 or 11 eggs. Here's the question:

The weights of eggs laid on a certain farm are normally distributed with a mean weight of 50 grams and standard deviation of 8grams.

a) How many of these eggs can we expect to weight at least 40 grams?

my answer: i found the probability which gives me 0.8943 round it off to 9
Books answer: 10 or 11

Am i wrong?