10 points! I know the answer, but I don't understand why. Can you please explain why the interest rate is 4 percent?
After 3 years, a $1,500 investment is worth $1,680. What is the interest rate on the investment?

Respuesta :

Because, after 3 years 1500+(3*60) is 1680! Hope this helped! Brainliest is always appreciated.
The amount of interest is the increase in the account: $1680 -1500 = $180.

Simple interest is computed by
  I = Prt
You have I = 180, P = 1500, t = 3 and you want to find r. Put the numbers in the formula and solve.
  180 = 1500*r*3
  180 = 4500*r
  180/4500 = r = 0.04

Of course, you know that 0.04 = 4/100 = 4%.