Question 1053460
Let {{{ a }}} = father's age now
Let {{{ b }}} = son's age now
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{{{ a - 10 = 2*( b - 10 ) + 35 }}}
{{{ a - 10 = 2b - 20 + 35  }}}
(1) {{{ a = 2b + 25 }}}
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Let {{{ n }}} = the number of years from
now when The father is twice the age
of the son
{{{ a + n = 2*( b + n ) }}}
{{{ a + n = 2b + 2n }}}
(2) {{{ n = a - 2b }}}
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Substitute (1) into (2)
(2) {{{ n = 2b + 25 - 2b }}}
(2) {{{ n = 25 }}}
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In 25 years the father will be twice the age of the son
( definitely get a 2nd opinion on this )