find the required annual rate to the tenth of a percent for $1500 to grow to $2400 if the interest is compounded quarterly for 7 years

New grandparents decide to invest 3200 per month in an annuity for their grandson, The account will pay interest per year which is compounded monthly. How much will be in the child's account at his twenty-first birthday?

Alejandro deposits $80 of his monthly earnings into an annuity that earns 6.25% annual interest, compounded monthly. How much money will he have saved after 5 years?