Question 312273
train A leaves 9.00am at 60 mph.
Train B leaves at 12 noon at 75 mph
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Before train B leaves train A has traveled 60*3 = 180 miles.
From this point let train A travel x miles before they meet.
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So train B travels x+180 miles to catch up.
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time taken by train A = x/60
time taken by train B = x+180 / 75
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x/60 = x+180 / 75
75x = 60(x+180)
75x=60x +10800
15x=10800
x= 720 miles.
Train B has to travel 720 miles to catch up.
its speed is 75 mph
time taken = 720/75
=9.6 hours