<PRE><B>Question 775159</B>
Q:
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? 
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A:
Let x be the number of hours after 10:30 am (time)
Equation: 560x + 640x = 2100
          1200x = 2100
          x = 2100/1200 
          x = 1.75 hours
1.75 hours = 1 hour and 45 minutes
10:30 am + 1 hour + 45 minutes = 12:15 pm
Answer: 12:15 pm </PRE>