Question 1009872
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A pilot flew a jet from City A to City B, a distance of 2200 mi. On the return trip, the average speed was 20% faster 
than the outbound speed. The round-trip took 8 h 20 min. What was the speed from City A to City B?
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Let u be the speed from City A to City B, in mph.

Then the speed on the return trip was 1.2u.

Time spent for the trip from A to B was {{{2200/u}}} hours.

Time spent for the trip from B to A was {{{2200/(1.2u)}}} hours.

An equation is 

{{{2200/u}}} + {{{2200/(1.2u)}}} = {{{8}}}{{{1/3}}},   or

{{{2200/u}}} + {{{2200/(1.2u)}}} = {{{25/3}}}.

Simplify and solve it for u.

As the first step, multiply both sides by 3*1.2*u.
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