Question 816029
r+p=280
r=280-p
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2.05r+2.75p=637
2.05(280-p)+2.75p=637
574-2.05p+2.75p=637
0.70p=637-574
0.70p=63
p=63/0.70
p=90 gal premium
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2.05r+2.75*90=637
2.05r=637-247.5
r=389.5/2.05
r=190 gal regular