Question 1149427
Let {{{ a }}} = ounces of water needed
Let {{{ b }}} = ounces of 30% solution needed
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(1) {{{ a + b = 150 }}}
(2) {{{ .3b / 150 = .2 }}}
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(2) {{{ .3b = 30 }}}
(2) {{{ b = 100 }}}
and
(1) {{{ a + 100 = 150 }}}
(1) {{{ a = 50 }}}
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50 ounces of water is needed
100 ounces of 30% solution is needed
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check:
(2) {{{ .3b / 150 = .2 }}}
(2) {{{ .3*100 / 150 = .2 }}}
(2) {{{ 30/150 = .2 }}}
(2) {{{ .2 = .2 }}}
OK