A car cover first half of the distance with 60kmph and
second half of the distance with 40kmph what is the average
speed?
Answers were Sorted based on User's Feedback
Answer / ranganathappa c
we know that speed=distance travelled/time taken
let the total distance travelled by the car is 2x km.
then time taken by it to cover first half is x/60 hour.
and for second half is x/40 hour.
then average speed= total distance travelled/ total time
taken.
=2x/[(x/60)+(x/40)]
=2x/[5x/120] (on simplification)
=48 kmph
| Is This Answer Correct ? | 195 Yes | 20 No |
Answer / mallikarjun angadi
1/60+1/40 = 2/x
100x = 4800
x = 4800/100
= 48kmph
| Is This Answer Correct ? | 92 Yes | 8 No |
Answer / khushboo gambhir
using concept f harmonic mean,which is used to calculate
most of the questions regarding average speeds for different
or the same portion of distance covered with different speeds.
we get average speed=2x/((x/60)+(x/40))
we get answer,48.
statistics student must have done this prob in oral.
| Is This Answer Correct ? | 51 Yes | 11 No |
Answer / divyanshu
d/40 +d/60 =2d/a
1/40 +1/60 =2d/a
3a+2a=120 (2)
5a=240
a=240÷5
a=48km hrs
| Is This Answer Correct ? | 12 Yes | 6 No |
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