Subject: General Aptitude · Chapter: Races and Games of Skill · Exam: · Marks: · Difficulty:
In a 500 m race, the ratio of the speeds of two contestants $A$ and $B$ is 3 : 4. If A has a start of 140 m, then A wins by
(a)60 m
(b)40 m
(c)20 m
(d)10 m
Answer
Answer (as printed): C
Explanation
To reach the winning post $A$ has to cover $$=(500-140) \mathrm{m}=360 \mathrm{m} .$$ While $A$ covers 3 m, $B$ covers 4 m. While $A$ covers $360 \mathrm{m}, B$ covers $\left(\frac{4}{3} \times 360\right) \mathrm{m}=480 \mathrm{m}$. Thus, when $A$ reaches the winning post, $B$ covers 480 m . $$\therefore A \text { wins by }(500-480) \mathrm{m}=20 \mathrm{m} .$$