Answer: They will drive 224 miles
Explanation: We know that they can drive 112 miles on 4 gallons
We set that up as 112/4 (miles per gallon)
8 is 4 twice, in other words, 4 times 2
So now we can see that 112 ?
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4 8
You do what you did on the bottom (times 2 to get 8) to the top (times 2 to get 224)
Hope this helps!