A, B, C and D purchase a gift worth ₹60. A pays $\tfrac{1}{2}$ of what others are paying, B pays $\tfrac{1}{3}$ of what others are paying, and C pays $\tfrac{1}{4}$ of what others are paying. What is the amount paid by D?
Phrases like "pays $\frac{1}{k}$ of what others are paying" translate to $x=\frac{1}{k}(S-x)$ where $S$ is the total. Solve each to get $x$ directly.
₹14
₹15
₹16
₹13