The formula I'm given: .Factory makes 1600 products each day.

Probability of a flawed product is 10%.

What is the probability of more than 175 flawed products?

Plugging in:

Which isnot even close to a given solution: "Laplace's approximation for P(175 < X) = 0.10565". (Which is close to second .)

The correct solution is , so I must be doing something wrong.

SOLVED: I was plugging in variance instead of standard deviation.