see below

Asked by  | 6th Mar, 2013, 10:40: AM

Expert Answer:

let initial speed was=v k.m. /hour
so time taken by plane with this speed=15000/v
time remain same so now time taken with increased speed=(15000/v+100)+1/2 hour
              (15000/v)-(15000/v+100)=1/2
solving this v=
v=500 K.M./Hour only if distance was 1500 k.m.

Answered by  | 6th Mar, 2013, 12:12: PM

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