How long will it take $5,000 to double itself if it is invested at 5% simple interest

Question

Need to set up an equation.

Answer 1

I will assume you meant 5% simple interest per annum.

Let x be the number of years needed.

The equation will be:

5000 + (0.05x)*(5000) = 2*5000

Solving it, we will get:

5000 + 250x = 10000
250x = 10000 - 5000
250x = 5000
x = 5000 / 250
x = 20

Hence, it will take 20 years for $5000 to double itself.