Question 661394
Henry can ride his horse at 4mph and get to the battlefield on time. If he stops for 1 hour to make a speech to his troops, he must ride 5mph for the whole trip to get to the battlefield on time. How far is it to the battlefield? 
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Let distance to the battlefield be "x":
No-delay DATA:
rate = 4 mph ; time = d/r = x/4 hrs
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With-delay DATA:
rate = 5 mph ; time = d/r = x/5 hrs
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Equation:
no-delay time = delay-time + 1
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x/4 = (x/5)+1
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5x = 4x + 20
x = 20 miles (distance to the battlefield)
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Cheers,
Stan H.
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