<PRE><B>Question 861393</B>
D=RT
LET X BE THE SPEED OF THE SLOWER TRAIN
LET X+10 BE THE SPEED OF THE FASTER TRAIN
720=(X+X+10)6
720=(2X+10)6
720=12X+60
12X=720-60
12X=660
X=660/12
X=55 MPH FOR THE SLOWER TRAIN.
55+10=65 MPH FOR THE FASTER TRAIN.
PROOF:
720=(55+65)6
720=120*6
720=720
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