Subject: General Aptitude · Chapter: Ratio and Proportion · Exam: · Marks: · Difficulty:
There are 420 coins consisting of one-rupee coins, 50-paise coins and 25-paise coins. If the ratio of their values be 2 : 3 : 5, then the number of one-rupee coins is
(a)20
(b)30
(c)90
(d)300
Answer
Answer (as printed): B
Explanation
Let the values of one-rupee, 50-paise and 25-paise coins be ₹ $2 x$, ₹ $3 x$ and ₹ $5 x$ respectively. Then, number of one-rupee coins $=2 x$; number of 50 -paise coins $=\frac{3 x}{0.5}=6 x$; number of 25-paise coins $=\frac{5 x}{0.25}=20 x$. $$\therefore 2 x+6 x+20 x=420 \Leftrightarrow 28 x=420 \Leftrightarrow x=15 .$$ Hence, number of one-rupee coins $=2 \times 15=30$.
Explanation as extracted from the printed page; notation may be imperfect.