The ratio between the profit of P and Q is 7 : 5 and, Q and R is 15  : 10. If the time period of P, Q and R is 1 year, 2 years, and 5 years. Find the ratio of their investment.

42 : 15 : 04

Profit ratio:

P : Q = 7 : 5 or ⇒ 21 : 15   (multiply by 3)

Q : R = 15 : 10

Now,

                P   :   Q   :    R

Profit →  21  :   15  :   10

Time →    1   :    2   :    5   

Inv.  →   \(\frac{21}{1}\)   :   \(\frac{15}{2}\)   :  \(\frac{10}{5}\)               [Inv. = \(\frac{Profit}{Time}\)]

⇒            42   :   15   :   4