To find how much gasoline costs each mile, you do 485/500. Reduce it to 97/100, or 97 cents. So .97m = c. B. Replace m with 1200 to get .97(1200) = c. C, after doing the math, you get 1164 dollars. C. Replace c with 820. Your equation is .97m = 820. Divide both sides by .97 to get m = about 845.36 to the nearest hundredth, 845.4 to nearest tenth, or 845 to the nearest whole mile. I recommend using the nearest hundredth to be precise, but that's up to you.
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