SOLUTION: An athlete runs for 2 hours and walks for 1 hour to cover a distance of 40km. If he runs for 2.5 hours and walks for 0,5 hours he covers 45km. Calculate his running speed and his w

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Question 1141760: An athlete runs for 2 hours and walks for 1 hour to cover a distance of 40km. If he runs for 2.5 hours and walks for 0,5 hours he covers 45km. Calculate his running speed and his walking speed. You may assume that each is constant.
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
           SPEED     TIMES     TIMES

WALK       w           1        0.5

RUN        r           2        2.5

DISTANCES             40       45

system%28w%2B2r=40%2Cw%2F2%2B2.5r=45%29

Multiply the "45" equation by 2:
system%28w%2B2r=40%2Cw%2B5r=90%29

E2-E1
3r=50
r=50%2F3
highlight%28r=16%262%2F3%29

w=40-2r
w=40-2%2816%262%2F3%29
40-32%264%2F3
40-33%261%2F3
highlight%28w=6%262%2F3%29