He played 5% if im correct
3.15 /7 = 0.45
3.20/8 = 0.40
4.10/10 = 0.41
4.80/16 = 0.3
Answer is 1. 7 stamps worth 3.15
Amount= Deposit or initial amount ( 1+ percent increase) ^period of time
So Amount= 50(1+0.1)^3
= 50(1.1)^3
= 50(1.331)
=66.55
So she will have $66.55 in 3 years.
