Delaney is saving money in an account that offers 8% simple interest. She deposits $\$2,000$ from her grandmother into the account and makes no additional deposits or withdrawals. How many years will it take to grow to $\$4,700$? Round to the nearest whole year.
We can use
A = P + Prt
Where A is the final amount, P = the original amount, r =the interset rate as a decimal, t = the time in years
4700 =2000 + 2000 (.08) t subtract 2000 from both sides
2700 = 2000 (.08)t
2700 = 160 t divide both sides by 160
2700 / 160 = t = 16.875 yrs = 17 yrs (rounded)