Question 621574
Let {{{ a }}} = amount invested losing 6%
Let {{{ b }}} = amount invested making 9%
given:
(1) {{{ a + b = 6000 }}}
(2) {{{ -.06a + .09b = 327 }}}
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(2) {{{ -6a + 9b = 32700 }}}
Multiply both sides of (1) by {{{6}}},
then add the equations
(1) {{{ 6a + 6b = 36000 }}}
(2) {{{ -6a + 9b = 32700 }}}
{{{ 15b = 68700 }}}
{{{ b = 4580 }}}
and since,
(1) {{{ a + b = 6000 }}}
(1) {{{ a + 4580 = 6000 }}}
(1) {{{ a = 1420 }}}
The amount invested losing 6% was $1,420
The amount invested making 9% was $4,580
check answer:
(2) {{{ -.06*1420 + .09*4580 = 327 }}}
(2) {{{ -85.2 + 412.2 = 327 }}}
(2) {{{ 327 }}}
OK