The price of a stock is governed by a log normal distribution with the expected growth rate μ=.12, volatility, σ=.2. The initial price is $75.

I have already calcuated:

E(stock price after 6 months) = 79.64

V = 128.12

σ = 11.32

How do I show that the probability of a loss after 6 months is 0.3372?

Thanks.