Question 487208
Let {{{ a }}} = amount invested @ 6%
Let {{{ b }}} = amount invested @ 8%
given:
(1) {{{ a + b = 5000 }}}
(2) {{{ .06a + .08b = 380 }}}
----------------------
Multiply both sides of (2) by {{{ 100 }}}
Then multiply both sides of (1) by {{{ 6 }}}
Then subtract (1) from (2)
(2) {{{ 6a + 8b = 38000 }}}
(1) {{{ -6a - 6b = -30000 }}}
{{{ 2b = 8000 }}}
{{{ b = 4000 }}}
and, since
(1) {{{ a + b = 5000 }}}
(1) {{{ a + 4000 = 5000 }}}
(1) {{{ a = 1000 }}}
$4,000 was invested @ 8%
check:
(2) {{{ .06a + .08b = 380 }}}
(2) {{{ .06*1000 + .08*4000 = 380 }}}
(2) {{{ 60 + 320 = 380 }}}
(2) {{{ 380 = 380 }}}
OK