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Maths Puzzle
Numerical Ability
Three cars travelling along a road in the same direction are, at a certain moment, in the following positions in relation to one another. Andrews is a certain distance behind Brooks, and Carter is twice that distance in front of Brooks. Each car travels at its own uniform rate of speed, with the result that Andrews passes Brooks in seven minutes, and passes Carter five minutes later. In how many minutes after Andrews would Brooks pass Carter?
86
Read Solution (Total 1)
-
- Andrew speed : V1
Brooks speed: V2
Carter speed V3
In the initial position the distance (Andrew-Brooks) = d, the distance (Brooks- Carter) = 2d,
V1 = (d+x)/7 = d/7 + x/7
V2 = x/7
Means : V1 = V2+d/7 .......(1)
V1 = (3d+y)/12 = d/4 + y/12
V3 = y/12
Means: V1=V3+d/4 ..... (2)
From (1) & (2)
V2=V3 + 3d/28 ..... (3)
V2 = (2d+z)/t = 2d/t + z/t
V3=z/t
V2=V3 + 2d/t ....(4)
From (3) & (4):
t = 18 2/3
and T = 18 2/3 - 12 = 6 2/3
The answer is: 6 min 40 sec
Source:
https://www.weeklypuzzle.net/2020/09/the-03-cars-puzzle.html - 4 years agoHelpfull: Yes(0) No(0)
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