A can beat B in a 100-metre race by 10 metres. B can beat C in a 100-metre race by 10 metres. What is the ratio (tA : tB : tC), which are the respective times taken by A, B and C to complete the race?
Answer & explanation
Correct answer: option 4
Given,
B + 10 = A, C + 10 = B,
Therefore , A : B = 100 : 90
and B : C = 100 : 90,
⇒ A : B : C = 100 : 90 : 81
⇒ (tA : tB : tC) = \(\frac{1}{100}\) : \(\frac{1}{90}\) : \(\frac{1}{81}\)
⇒ LCM = 8100
⇒ Required ratio = 81 : 90 : 100.