In a family, the father took $\frac{1}{4}$ of the cake and he had 3 times as much as each of the other members had. The total number of family members is
(a)3
(b)7
(c)10
(d)12
Answer
Answer (as printed): C
Explanation
Let there be $(x+1)$ members. Then, $$\begin{aligned} & \text { Father's share }=\frac{1}{4} \text {, share of each other member }=\frac{3}{4 x} \text {. } \\ & \therefore \quad 3\left(\frac{3}{4 x}\right)=\frac{1}{4} \Leftrightarrow 4 x=36 \Leftrightarrow x=9 \text {. } \end{aligned}$$ Hence, total number of family members = 10.
Explanation as extracted from the printed page; notation may be imperfect.