Question

A man invested #20,000 in bank A and #25,000 in bank B at the beginning of a year. Bank A pays simple interest at a rate of y% per annum and B pays 1.5y% per annum. If his total interest at the end of the year from the two banks was #4,600 . Find the value of y.

Answer 1

Interest from bank A : $\dfrac{y}{100}\times 20000=200y$

Interest from bank A : $\dfrac{1.5y}{100}\times 25000=375y$

His total interest at the end of the year from the two banks

$$200y+375y=4600$$

Solve for $y$

$$575y=4600$$

$$y=\dfrac{4600}{575}$$

$$y=8$$