Answer:

Step-by-step explanation:
Since the question implies his truck travels at a constant distance per gallon, we can set up the following proportion to find how much father his truck can go.
Let
represent how much farther his truck can go, in kilometers:

Cross-multiplying, we get:

10*8=80
3*8=24
80-24=56
You would save $56.00 in 8 weeks
The answer is 7/5 th. You can add fractions without first having a common denominator so you would change the 8's by multiplying it by 5 to get 40 and you would multiply the 5 by 8 to get 40 as well. And the rule whatever you do to the bottom you have to do to the top so whatever you multiplied 8 by do the same for the numerator and whatever you multiplied 5 by you do the same for the numerator. So your new equation would be (75/40+16/40)+(-35/40). you would then add the numerator's across to get 56 and the denominator would stay the same so the answer is 56/40. But you have to now simplify 56/40 down to 14/10 and then once more to 7/5 which is the final answer.