Question 1040218
Let {{{ a }}} = liters of 15% solution needed
Let {{{ b }}} = liters of water needed
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(1) {{{ a + b = 6 }}}
(2) {{{  .15a / ( a + b ) = .1 }}}
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By substitution:
(2) {{{ .15a / 6 = .1 }}}
(2) {{{ .15a = .6 }}}
(2) {{{ a = 4 }}}
and
(1) {{{ a + b = 6 }}}
(1) {{{ 4 + b = 6 }}}
(1) {{{ b = 2 }}}
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4 liters of 15% solution are needed
2 liters of water are needed
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check:
(2) {{{  .15a / ( a + b ) = .1 }}}
(2) {{{  .15*4 / 6 = .1 }}}
(2) {{{ .6 = .6 }}}
OK