.
D1 = 100*t is the "distance" equation for the first train.
D2 = 90*t is the "distance" equation for the second train.
D1 + D2 = 456 (given) =====>
100t + 90t = 456 ====> (100+90)*t = 456 ====> 190t = 456 ====> t = hours = 2.4 hours = 2 hours and 24 minutes.
Solved.
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On Travel and distance problems, read the lessons
- Travel and Distance problems
- Travel and Distance problems for two bodies moving in opposite directions
- Travel and Distance problems for two bodies moving in the same direction (catching up)
in this site.