<PRE><B>Question 903031</B>
0.13*x+0.7*200=0.29(200+x)
0.13*x+140=58+0.29x
0.13x-0.29x=58-140
-0.16x=-82
x=512.5 gallons of 13% is added to 200 gallons of 70% to get  712.5 oz  at 29%
check
0.13*512.5+0.7*200=0.29(200+512.5)
66.625+140=0.29(712.5)
206.625=206.625
ok

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