While on a straight road, car X and car Y are traveling at different constant rates. If car X is now 1 mile ahead of car Y, how many minutes from now will car X be 2 miles ahead of car Y ?
(1) Car X is traveling at 50 miles per hour and car Y is traveling at 40 miles per hour.
(2) 3 minutes ago car X was 1/2 mile ahead of car Y.
OA is D
Rate time distance question
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You can solve this problem, if you know relative speed.
(1) relative speed = 40-30 = 10
(2). relative distance = 1 - (1/2) = 1/2 mile
relative speed = (1/2)(1/(3/60)) = 10
D is the answer.
10 miles per 60 minutes = 1 mile per every 6 minutes.
2 miles ahead, and currently 1 mile ahead. The relative distance = 1 miles. 6 more mins required.
(1) relative speed = 40-30 = 10
(2). relative distance = 1 - (1/2) = 1/2 mile
relative speed = (1/2)(1/(3/60)) = 10
D is the answer.
10 miles per 60 minutes = 1 mile per every 6 minutes.
2 miles ahead, and currently 1 mile ahead. The relative distance = 1 miles. 6 more mins required.