Question

the total cost of gasoline varies directly with the number of gallons purchased. Gas costs $1.89 per gallon. Write a direct variation to the model the total cost c for g gallons of gas

Answer 1

One gallon is $1.89

How much is two gallons of gas?

Answer 2

$3.78

Answer 3

good

we can write it as 1.89*2

Answer 4

for 3 gallons, we do

1.89*3 = 5.67

Answer 5

So far, we know that


1 gallon costs 1.89*1

2 gallons cost 1.89*2

3 gallons cost 1.89*3


see the pattern?

Answer 6

Yes i see...Can we write that as c = 1.89g ?

Answer 7

you got it

Answer 8

so g gallons cost 1.89g dollars

therefore

c = 1.89g

Answer 9

Thanks so much!

Answer 10

you're welcome...btw, you can tell this is a very old problem given the price of gas lol