Question 1070248
Let the rate for Collins family =
{{{ a/15 }}} L/hr
Let the rate for the Adams family =
{{{ b/25 }}} L/hr
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Given:
(1) {{{ a/15 + b/25 = 75 }}} L/hr
(2) {{{ a + b = 1475 }}}
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Multiply both sides of (1) by {{{ 75 }}}
(1) {{{ 5a + 3b = 5625 }}}
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Multiply both sides of (2) by {{{ 3 }}}
and subtract (2) from (1)
(1) {{{ 5a + 3b = 5625 }}}
(2) {{{ -3a - 3b = -4425 }}}
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{{{ 2a = 1200 }}}
{{{ a = 600 }}}
and
(2) {{{ a + b = 1475 }}}
(2) {{{ 600 + b = 1475 }}}
(2) {{{ b = 875 }}}
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Rate for Collins family:
{{{ 600/15 = 40 }}} L/hr
Rate for Adams family:
{{{ 875/25 = 35 }}} L/hr
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check:
(1) {{{ a/15 + b/25 = 75 }}} L/hr
(1) {{{ 40 + 35 = 75 }}}
(1) {{{ 75 = 75 }}}
OK
check the math