Your financial advisor is offering two investment plans. The return on these investments is normally distributed. Plan A has medium risk, meaning that there is some risk of losing some or all of your money. This plan claims an average return of 3% on your investment with a standard deviation of 0.1%. Plan B has high risk, meaning that there is a stronger chance that you could lose a significant portion of your investment. The plan claims to have an average return of 5% with a standard deviation of 1%.

While investigating these plans, you discover that out of a random sample of 100 people who invested in Plan A, 78% of them received an average return of 2.75% with a standard deviation of 0.25%. Out of a random sample of 100 people who invested in Plan B, 88% of them experienced an average return of 3.9% with a standard deviation of 1.2%.