my attempt at an answer to the train problem .... Q. Train A, traveling 50 miles per hour, leaves New York at 12:00pm heading toward Boston, 225 miles away. Train B, traveling 60 mph, leaves Boston at 12:30pm, heading toward New York. When do the two trains meet? A> amd explanation ... Let x to be the time train B travels
since Train A leaves ½ hour earlier, so Train A travels for (x+½ hours) or (x hours + 30min).
the formula we need for this question is: rate*time=distance (RxT=D)
so, for Train A, the distance it travels is 50(x+½)=D
for Train B, the distance it travels is 60(x)=D 60x=225, therefore x= 3 hours and 45 minutes ... and the distance is given as 225 ... since Train B has to catch up with Train A, their distance must be equal! Things equal to the same thing are equal to each other ... thus:::: so our equation would be 50(x+{½ hour})=60(x) or in expanded form ... 50x + 50*½ hour = 60x minus 50x from both sides ::: 50*½ hour= 10x 50 * ½ hours = 1500 minutes= 10x divide both sides by 10 and x=150, thus X=150 minutes
it will take train A, 3 hours to go 150 miles, (150/50= 3 hours)
and it will take train B, 2½ hours to go 150 miles, (150/60= 2½ hours) so they shall meet up at 3:00 PM .. hope this helps you ....actually i hope it is right ....
Last edited by Monday; 10-18-2007 at 04:52 PM.
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