Question

Veeru invested Rs 10000 at 5% simple annual interest, and exactly after two years, Joy invested Rs 8000 at 10% simple annual interest. How many years after Veeru's investment, will their balances, i.e., principal plus accumulated interest, be equal?

Answer 1

Let after $n$ years both the sums amount to the equal amounts.
Then, $1000\bigg(\frac{1+5×(n+2)}{100}\bigg) = 800\bigg(1+10×\frac{n}{100}\bigg)$

i.e., $1.5 = \frac{15n}{100} ⇒ n =10$

Hence 12 years after veeru invested their balances will be equal.