Question 1024936
Let {{{ m }}} = Mary's age
Let {{{ j }}} = Jane's age
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(1) {{{ m  = j + 5 }}}
(2) {{{ 4j + 3 = 3m - 2 }}}
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(2) {{{ 3m - 4j = 5 }}}
and
(1) {{{ m - j = 5 }}}
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Multiply both sides of (1) by {{{ 3 }}}
and subtract (2) from (1)
(1) {{{ 3m - 3j = 15 }}}
(2) {{{ -3m + 4j = -5 }}}
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{{{ j = 10 }}}
and
(1) {{{ m  = j + 5 }}}
(1) {{{ m  = 10 + 5 }}}
(1) {{{ m = 15 }}}
Mary is 15
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check:
Four times Jane's age increased by 3 years is
{{{ 4*10 + 3 = 43 }}}
equals three times Mary's age less 2 years
{{{ 3*15 - 2 = 43 }}}
OK