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Old 10-18-2007, 04:48 PM   #12
Monday
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Location: Long Island
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Default 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 ....

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Last edited by Monday; 10-18-2007 at 04:52 PM.
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