10 is not a perfect square I believe
0.84(because 20% of the observations are about 0.84)
You've found the 80th percentile! The 80th percentile of the standard normal distribution is 0.84. That's because 80% of the observations fall below 0.84. (Note: The 80th percentile of every normal distribution is 0.84 times the standard deviation above the mean.)
The answer is 1.10 because you have $90 you give away fifty
