<PRE><B>Question 1115124</B>
40x+(40*6) = 60x
40x+240 = 60x
240 = 20x
reverse the equation to have the unknown on the left:
20x = 240
x = 240/20 = 12
It will take train B 12 hours to catch up train A
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Check:
40x+(40*6) = 60x
40(12)+(40*6) = 60(12)
480+240 = 720 Correct
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