Question 884450
Let {{{ a }}} = liters of 8% acetic acid from the barrel needed
Let {{{ b }}} = liters of pure water to be added
{{{ .08a }}} = liters of acetic acid taken from the barrel
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(1) {{{ a + b = 64 }}}
(2) {{{ .08a / 64 = .05 }}}
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(2) {{{ .08a = .05*64 }}}
(2) {{{ a = 3.2 / .08 }}}
(2) {{{ a = 40 }}}
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(1) {{{ 40 + b = 64 }}}
(1) {{{ b = 24 }}}
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40 liters of vinegar from the barrel and 24 liters
of pure water should be combined
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check:
(2) {{{ .08*40 / 64 = .05 }}}
(2) {{{ 3.2/64 = .05 }}}
(2) {{{ 3.2 = .05*64 }}}
(2) {{{ 3.2 = 3.2 }}}
OK