Normal Approximation

A manufacturer claims that he makes light bulbs each of which has a 0.9 probability
of operating successfully when plugged in.

a. If 1000 light bulbs are tested what is the mean and standard deviation for this binomial probability function?
for this problem I'm getting 900 for the mean and 9.486 for the standard deviation

b. In the test of the 1000 bulbs 117 were defective when plugged in. What is the probability that 117 or fewer would be defective? (Use the normal approximation to the binomial probability function)

I get a really weird answer for this problem. for the z score I'm getting a -82.