<PRE><B>Question 146919</B>
Distance(d) equals Rate(r) times Time(t) or d=rt;  r=d/t and t=d/r

Let d=distance that the boy rides away

Time to ride away =d/10
Time to ride back =d/9

Now we are told that time to ride away plus time to ride back equals 9.5 hrs.  So our equation to solve is:


d/10 + d/9 = 9.5  multiply each term by 90
9d+10d=855  collect like terms
19d=855  divide each side by 19

d=45 km-------------distance that the boy rides away


CK

45/10+45/9=9.5
4.5+5=9.5
9.5=9.5


Hope this helps ---------------ptaylor

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