GRE
Exam
Numerical Ability
Time Distance and Speed
A train travels from a to b at the speed of 20kmph and from b to a at the speed of 30kmph. then what is the average speed to train in kmph
Read Solution (Total 2)
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- ave speed = (d+d)/(d/s1 + d/s2) = 2/(1/s1 + 1/s2) = 2*s1*s2/(s1+s2)
where d=distance & s1,s2 are speeds of train
ave speed = 2*20*30/(20+30)= 2*20*30/50 = 24 km/h - 10 years agoHelpfull: Yes(0) No(0)
- Avd speed = Total distance travelled / Total time taken= (d+d)/(d/s1 + d/s2) = 2/(1/s1 + 1/s2) =2x/x/20+x/30=24KMPH
- 7 years agoHelpfull: Yes(0) No(0)
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