A family has two cars. The first car has a fuel efficiency of
35
miles per gallon of gas and the second has a fuel efficiency of
20
miles per gallon of gas. During one particular week, the two cars went a combined total of
1575
miles, for a total gas consumption of
60
gallons. How many gallons were consumed by each of the two cars that week?

Question

A family has two cars. The first car has a fuel efficiency of 
35
miles per gallon of gas and the second has a fuel efficiency of
20
 miles per gallon of gas. During one particular week, the two cars went a combined total of 
1575
 miles, for a total gas consumption of 
60
 gallons. How many gallons were consumed by each of the two cars that week?

dtan5457 · Answer

quick note that's not the best way to format your question lol

michele_laino · Answer

I think if I call with x number of gallon used by the first car and with y number og gallon used by the second car, then from your data I can write this:
$$35*x+20*y=1575$$
and
$$x+y=60$$
I simply mathematized your problem text!

dtan5457 · Answer

Going on from @Michele_Laino 

Now, solve it like a system of equations

35x+20y=1575

x+y=60
^^^^^

smart choice to isolate one of the variables on the 2nd equation

dtan5457 · Answer

To plug into the first ^

dtan5457 · Answer

Do you know how to do that?

dtan5457 · Answer

@autumnshadow