A is twice fast as B and B is thrice fast as C. The journey covered by C in 78 minutes will be covered by A in :
A. 13 min
B. 15.5 min
C. 17 min
D. 12 min
Answer: Option A
Solution(By Examveda Team)
The ratio of speeds of A, B, C = 6 : 3 : 1 The ratio of time taken by A, B, C = $$\frac{1}{6}$$ : $$\frac{1}{3}$$ : 1To simplify it, we will multiply it by LCM of ratio of speeds given.
Hence, the ratio of time taken by A, B, C = 1 : 2 : 6 [Speed is inversely proportional to time, means if speed increase time decreases. So, ratio of time would be reciprocal of the ratio of speed given. ]
Time taken by C to covered given distance = 78 = 6 × 13
The ratio of time of A and C = 1 : 6
Thus, time taken by A = 13 min.
Join The Discussion
Comments ( 2 )
Related Questions on Speed Time and Distance
A. 48 min.
B. 60 min.
C. 42 min.
D. 62 min.
E. 66 min.
A. 262.4 km
B. 260 km
C. 283.33 km
D. 275 km
E. None of these
A. 4 hours
B. 4 hours 30 min.
C. 4 hours 45 min.
D. 5 hours
SPEED RATIO=A:B:C=6:3:1
TIME RATIO =1:2:6[LCM OF[ 6,3 &1=6]
SO 6 FOR 78
1 FOR 78/6=13...(ANS)
i want clear explanation