Question 770456
Let {{{ a }}} = ml of solution A needed
Let {{{ b }}} = ml of solution B needed
{{{ .17a }}} = ml of alcohol in solution A
{{{ .14b }}} = ml of alcohol in solution B
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(1) {{{ a = 3b }}}
(2) {{{ .17a + .14b = 195 }}}
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(2) {{{ 17a + 14b = 19500 }}}
Substitute (1) into (2)
(2) {{{ 17*( 3b ) + 14b = 19500 }}}
(2) {{{ 51b + 14b = 19500 }}}
(2) {{{ 65b = 19500 }}}
(2) {{{ b = 300 }}}
He should use 300 ml of solution B
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check:
(1) {{{ a = 3b }}}
(1) {{{ a = 900 }}}
and
(2) {{{ .17a + .14b = 195 }}}
(2) {{{ .17*900 + .14*300 = 195 }}}
(2) {{{ 153 + 42 = 195 }}}
(2) {{{ 195 = 195 }}}
OK