Question 571445
{{{ f }}} = Father's age now
{{{ s }}} = Son's age now
{{{ f - 20 }}} = Father's age 20 yrs ago
{{{ s - 20 }}} - Son's age 20 yrs ago
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given:
(1) {{{ f = 2s }}}
(2) {{{ f - 20 = 12*( s - 20 ) }}}
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(2) {{{ f - 20 = 12s - 240 }}}
(2) {{{ 12s - f = 220 }}}
Substitute (1) into (2)
(2) {{{ 12s - 2s = 220 }}}
(2) {{{ 10s = 220 }}}
(2) {{{ s = 22 }}}
and, since
(1) {{{ f = 2s }}}
(1) {{{ f = 2*22 }}}
(1) {{{ f = 44 }}}
The Father is 44 and the Son is 22