Question 1013784
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Julia Ling drove the 200 km to Richmond at a speed 10 km/h faster than usual. If she completed the trip in one hour less than usual, find her usual driving speed.
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Your equation is

200/u - 200/(u+10) = 1.

where u is the usual speed in {{{km/h}}}.

To solve it, multiply both sides by u*(u+1) to get off denominators.

Then simplify and solve.

<U>Answer</U>. 40 {{{km/h}}}.
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