<PRE><B>Question 353719</B>
After walking a distance of 6 miles at a certain rate, a man decided to increase his rate per hour by 1 mile and walked 5 miles farther. 
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Had he walked the entire distance of 11 miles at his former rate, his time would have been 15 minutes longer. Find his former rate.
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1st segment DATA:
distance = 6 miles ; rate = x mph ; time = 6/x hrs.
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2nd segment DATA:
distance = 5 miles ; rate = x+1 mph ; time = 5/(x+1) hrs.
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Total distance DATA:
distance = 11 miles ; rate = x ; time = d/r = 11/x hrs
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Equation:
(time + time) - time = (1/4)hrs
[11/x] -[6/x + 5/(x+1)] = 1/4
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Multiply thru by 4x(x+1) to get:
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11*4(x+1) - [6*4*(x+1) + 5*4x] = x(x+1)
44x+44 - 24x-24 - 20x = x^2+x
20 = x^2+x
x^2+x-20 = 0
(x+5)(x-4) = 0
Positive solution:
x = 4 mph
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Cheers,
Stan H.
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