Amy & Ashley bike along the same trail. Amy bikes the entire trail at 20mph & Ashley bikes at 15mph. Amy finishes 8 minutes before Ashley. How many miles long is the trail?
d/15 - d/20 = 8/60
4 d - 3 d = 8
d = 8
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then Amy takes (8/20)*60 =24 min
and Ashley takes (8/15)*60 =32min
Indeed difference of 8 min