Question 1066435
Let {{{ a }}} = ml of 26% solution needed
Let {{{ b }}} = ml of 47% solution needed
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(1) {{{ a + b = 70 }}}
(2) {{{ ( .26a + .47b ) / 70 = .32 }}}
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(2) {{{ .26a + .47b = .32*70 }}}
(2) {{{ .26a + .47b = 22.4 }}}
(2) {{{ 26a + 47b = 2240 }}}
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Multiply both sides of (1) by {{{ 26 }}}
and subtract (1) from (2)
(2) {{{ 26a + 47b = 2240 }}}
(1) {{{ -26a - 26b = -1820 }}}
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{{{ 21b = 420 }}}
{{{ b = 20 }}}
and
(1) {{{ a + 20 = 70 }}}
(1) {{{ a = 50 }}}
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50 ml of 26% solution are needed
20 ml of 47% solution are needed
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check:
(2) {{{ ( .26a + .47b ) / 70 = .32 }}}
(2) {{{ ( .26*50 + .47*20 ) / 70 = .32 }}}
You can finish this check