A began a business with Tk. 75000. He was joined afterwards by B with Tk. 37500. For how much period does B join, if the profits at the end of the year are divided in the ratio of 4 : 1?

Question: A began a business with Tk. 75000. He was joined afterwards by B with Tk. 37500. For how much period does B join, if the profits at the end of the year are divided in the ratio of 4 : 1?

Solution:
Suppose B joined for x months.

Then,
(75000 × 12)/(37500 × x) = 4/1
⇒ 4(37500 × x) = (75000 × 12)
⇒ x = (75000 × 12)/(37500 × 4)
∴ x = 6

So, B joined for 6 months.