SOLUTION: Kent drives his Mazda 110 miles in the same time that Dave drives his Nissan 100 miles. If Kent averages 5 miles per hour faster then Dave, find their rates?
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Question 134237: Kent drives his Mazda 110 miles in the same time that Dave drives his Nissan 100 miles. If Kent averages 5 miles per hour faster then Dave, find their rates?
You can put this solution on YOUR website! Distance(d) equals Rate(r) times Time(t) or d=rt; r=d/t and t=d/r
Let r=Dave's speed
Then r+5=Kent's speed
Amount of time that Kent drives=110/(r+5)
Amount of time that Dave drives=100/r
Now we are told that the above two times are equal, so:
110/(r+5)=100/r multiply each side by r(r+5) (or cross-multiply)
110r=100(r+5)
110r=100r+500 subtract 100r from each side
110r-100r=100r-100r+500 collect like terms
10r=500 divide both sides by 10
r=50 mph--------------------------Dave's speed
r+5=50+5=55 mph-----------------------Kent's speed
