Question 414153
Let {{{w}}} = gallons of water to be added
given:
{{{.85*300 = 255}}} are gallons of alcohol in 85% mixture
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{{{255/(w + 300) = .7}}}
{{{255 = .7*(w + 300)}}}
{{{255 = .7w + 210}}}
{{{.7w = 45}}}
{{{w = 64.286}}} gallons
64.286 gallons of water must be added