Please use Front Line Analytic solver.

If you dont have, excel built in solver would be fine

Lynn Price recently completed her MBA and accepted a job with an electronics manufacturing company. Although she likes her job, she is also looking forward to retiring one day. To ensure that her retirement is comfortable, Lynn intends to invest $3,000 of her salary into a tax-sheltered retirement fund at the end of each year. Lynn is not certain what rate of return this investment will earn each year, but she expects each year's rate of return could be modeled appropriately as a normally distributed random variable with a mean of 12.5% and standard deviation of 2%. How much should Lynn invest each year if she wants there to be a 90% chance of having at least $1 million in her retirement fund at age 60