Question 1093259
Let {{{ a }}} = man's age now
Let {{{ b }}} = son's age now
{{{ a + 10 }}} = man's age in 10 yrs
{{{ b + 10 }}} = son's age in 10 yrs
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(1) {{{ a = b + 24 }}}
(2) {{{ a + 10 = 3*( b + 10 ) }}}
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(1) {{{ a - b = 24 }}}
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(2) {{{ a + 10 = 3b + 30 }}}
(2) {{{ a - 3b = 20 }}}
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Subtract (2) from (1)
(1) {{{ a - b = 24 }}}
(2) {{{ -a + 3b = -20 }}}
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{{{ 2b = 4 }}}
{{{ b = 2 }}}
The son is 2 yrs old
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check:
(1) {{{ a - b = 24 }}}
(1) {{{ a - 2 = 24 }}}
(1) {{{ a = 26 }}}
and
(2) {{{ a - 3b = 20 }}}
(2) {{{ a - 3*2 = 20 }}}
(2) {{{ a = 26 }}}
OK