Question

Solve the problem.

The formula A = P(1 + r)^2 is used to find the amount of money, A, in an account after P dollars have been invested in the account paying an annual interest rate, r, for 2 years. Find the interest rate r if $500 grows to $980 in 2 years.
Seleccione una respuesta.
a. 96%
b. 4%
c. 240%
d. 40%

Answer 1

980=500(1+r)^2 divide by 500 to get 1.96=(1+r)^2 take the square root of both sides to get 1.4=1+r. Subtract 1 to get r=.4 and that in percent is 40% so answer choice D is correct.

Answer 2

are you sure?

Answer 3

Yes, if you aren’t just plug it back in to the equation and see if I’m right.

Answer 4

40 % is correct; i made a mistake earlier; my apologies