Jan and Jake use the same taxi cab service. Jan pays $12 for 12 miles and Jake pays $9 for 8 miles. Find the price per mile the cab company charges. Cost per mile = ?

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Answer 1 · 2018-03-18T23:26:43

cost per mile: total cost/miles

If they were to ask a basic fee:

$$12=12$ miles
$$9=8$ miles

So $12-$9=3$
There is an increase of $$3= $12-$8$ = on $4$ miles

So each mile costs $3/4= $0.75$

With a basic fee: $12$ miles will cost: $12 xx0.75= 9$

$$12-$9=$3$ basic fee

Check:
$8xx0.75=6$

$6+3$ basic fee= $$9$

And that adds up for Jake.

With algebra:

$(Delta y) / (Delta x)$

$(12-9 =3 (Delta y))/(12-8 =4 (Delta x))$

So it's $y=3/4x+b$

$12=3/4xx12+b$

$12=9+b$

$b=12-9$

$b=3$

$y=3/4x+3$