Question 1103192
Let {{{ I }}} = interest earned @ 5%
{{{ 3420 - I }}} = interest earned @ 7%
Let {{{ P }}} = Amount invested @ 5%
{{{ 60000 - P }}} = amount invested @ 7%
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{{{ I = P*r*t }}}
(1) {{{  I = P *.05*1 }}}
(2) {{{ 3420 - I = ( 60000 - P )*.07*1 }}}
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Plug (1) into (2)
(2) {{{ 3420 - .05P = 4200 - .07P }}}
(2) {{{ .02P = 780 }}}
(2) {{{ P = 39000 }}}
and
{{{ 60000 - P = 60000 - 39000 }}}
{{{ 60000 - P = 21000 }}}
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She invested $39,000 @ 5% and
$21,000 @ 7%
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check:
(1) {{{ I = .05*39000 }}}
(1) {{{ I = 1950 }}}
and
(2) {{{ 3420 - I = 21000*.07 }}}
(2) {{{ 3420 - I = 1470 }}}
(2) {{{ I = 1950 }}}
OK