Anis's and Bulbul's shares in a business are in the ratio of 5 : 3. If Anis has invested Tk. 70000 for 12 months, for what period Bulbul has invested Tk. 60000?

Question: Anis's and Bulbul's shares in a business are in the ratio of 5 : 3. If Anis has invested Tk. 70000 for 12 months, for what period Bulbul has invested Tk. 60000?

Solution:
Let,
Bulbul has invested for x months
Anis : Bulbul = (70000 × 12) : (60000 × x) = 5 : 3
⇒ 84 : 6x = 5 : 3
⇒ 14 : x = 5 : 3
⇒ 14/x = 5/3
⇒ 5x = 42
⇒ x = 42/5
∴ x = 8.4