If the Hans leave for 3 days, and Tish wants to feed the dogs 3 cans each day, we can solve this problem using simple multiplication.
3 days * 3 cans / 1 day = 9 cans
This is how I'd set it up:
405/20 = 243/x
this means the mpg (miles / gallons) for 1 situation is the same as the mpg for the other situation (because the rate is the same)
then just cross multiply and solve:
405x=243*20 or 405x=4860 or x = 12
he would need 12 gallons of gas for 243 miles
Answer: x=-1
Step-by-step explanation:
8-3x-x=12
-3x-x=-4x
8-4x=12
-8 -8
-4x=4
-4x/-4=4/-4
x=-1