Question 987260
Each taxi travels 7 kilometers more than each car.
Together, the 5 taxis travel {{{ 7*5 = 35 }}} mi more than
the 4 cars
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Let {{{ d }}} = the distance traveled by the 4 cars
{{{ d + d + 35 = 125 }}}
{{{ 2d = 90 }}}
{{{ d = 45 }}}
and
{{{ d + 35 = 80 }}}
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For the 4 cars:
{{{ 45*( 1/10 ) = 4.5 }}} liters
The cars use 4.5 liters of gas in 1 day
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I'm not sure about the wording of th last sentence.
"How much gas do THE CARS use in a day if THEY use 
1 liter of gas for every 10 kilometers traveled?"
All 4 cars together?
Just 1 car?
I solved it  for all 4 cars together
You might want another opinion