Question

How many years will it take for $4,000 to double at a simple interest rate of 5%?​ Show your work.

Answer 1

Answer: in explination

Step-by-step explanation:

annual interest = .05(4000) = 200  

to double, you need another $4000  

number of years = 4000/200 = 20  

annual interest = .05(4000) = 200  

to double, you need another $4000  

number of years = 4000/200 = 20  

it will take 20 years  

to check if you are right you would...

Check:

simple interest on $4000 for 20 years at 5%  

= .05(20)(4000) = 4000  

the amount = what we had + new amount  

= 4000 + 4000 = 8000 which is double what we started with  

So the answer would be it took 20 years.