Two cars are traveling on the same road towards each other. If car A

Question

Two cars are traveling on the same road towards each other. If car A is traveling at a speed of 120 Km/h and car B is traveling 15% slower, how much time will it take the cars to meet if the initial distance between the two is 668.4 Km and car A started to drive one hour and a half before car B started?

A. one hours and 30 minutes.
B. two hours.
C. two hours and 12 minutes.
D. three hours and 15 minutes.
E. three hours and 18 minutes.

A. one hours and 30 minutes.
B. two hours.
C. two hours and 12 minutes.
D. three hours and 15 minutes.
E. three hours and 18 minutes.

Archit3110 · Answer

net relative speed of A&B ; 120+120*.85 ; 222 kmph
and distance covered by A in 3/2 hrs ; 3/2*120 ' 180 kms 
so net distance left ; 668.4-180 ; 488.4 km
time taken would be 488.4/222 ; 2 hrs 12 mins
IMO C

dcummins · Answer

First determine the rates.
85/100 * 120 = 102km

The distance at which the two objects meet is equal to the sum of each individual objects distance travelled.
RateA*Time Travelled A + Rate B* Time Travelled(B) = Distance that separated the two items

120T + 1.5*120 + 102T = 688.4
222T = 668.4-180
222T = 488.4 (I converted to a fraction to make it easier)
222T = 4884/10
2220T =4884
1110T = 2442
T = 2442/ 1110 = 2.2
without doing any further calculations we can see that we have 2 hours + some change, so the only answer that gets this is C

ScottTargetTestPrep · Answer

Since car A is traveling at a rate of 120 km/h, car B is traveling at a rate of 0.85 x 120 = 102 km/h. So we can create the equation:

120(t + 1.5) + 102t = 668.4

120 t + 180 + 102t = 668.4

222t = 488.4

t = 488.4/222 = 2.2 hours = 2 hours and 12 minutes

Answer: C

ummekazi · Answer

I think correct answer is 2 hours 13 minutes

Kinshook · Answer

Given: Two cars are traveling on the same road towards each other.

Asked: If car A is traveling at a speed of 120 Km/h and car B is traveling 15% slower, how much time will it take the cars to meet if the initial distance between the two is 668.4 Km and car A started to drive one hour and a half before car B started?

Speed of car A = 120 km/h
Speed of car B = 85% * 120 = 102 km/h

Initial distance = 668.4 km
Distance travelled by Car A in 1.5 hr = 120 * 1.5 = 180 km

Distance remaining when both car A & car B are travelling = 668.4 - 180 = 488.4 km
Relative speed = 120 + 102 = 222 km/h
Time taken to cover the distance = 488.4 /222 = 2.2 hours = 2 hours 12 mins

IMO C

Kinshook · Answer

Bunuel 
it is not very clear whether total time when car A started or the time when car B started is asked in the question.
Please check and correct

bumpbot · Answer

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Two cars are traveling on the same road towards each other. If car A

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Two cars are traveling on the same road towards each other. If car A

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