<PRE><B>Question 495388</B>
At 10:30 am two planes leave Houston, one flying east at 560 km/h and the other flying west at 640 km/h. At what time will they be 2100 km apart? 
I have tried using a chart 
Rate x Time = Distance
Plane 1: 640 x 

Plane 2: 560 x 
640x+ 560x= 2100 
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1200x = 2100
x = 21/12
x = 7/4 hrs = 1.75 hr = 1 hr 45 minutes
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Time: 10:30 + 1 hr 45 = 12:15 pm
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Cheers,
Stan H.
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