Question

9400 dollars is placed in an account with an annual interest rate of 6.25%. To the nearest tenth of a year, how long will it take for the account value to reach 47100 dollars?

Answer 1

Answer:

$t=64.2\ years$

Step-by-step explanation:

we know that

The simple interest formula is equal to

$A=P(1+rt)$

where

A is the Final Investment Value

P is the Principal amount of money to be invested

r is the rate of interest  

t is Number of Time Periods

in this problem we have

$t=?\ years\\ P=\ 9,400\\ A=\ 47,100\\r=6.25\%=6.25/100=0.0625$

substitute in the formula above

$47,100=9,400(1+0.0625t)$

solve for t

$t=[(47,100/9,400)-1]\0.0625$

$t=64.2\ years$