Question 476003
Let {{{a}}} = amount invested @ 4% per yr
Let {{{b}}} = amount invested @ 5% per yr
given:
(1) {{{ a + b = 8000 }}}
(2) {{{ .04a + .05b = 380 }}}
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(2) {{{ 4a + 5b = 38000 }}}
Multiply both sides of (1) by {{{4}}} and subtract from (2)
(2) {{{ 4a + 5b = 38000 }}}
(1) {{{ -4a - 4b = 32000 }}}
{{{ b = 6000 }}}
and
(1) {{{ a + b = 8000 }}}
(1) {{{ a + 6000 = 8000 }}}
(1) {{{ a = 2000 }}}
$2,000 is invested @ 4% per yr
$6,000 is invested @ 5% per yr