Question 1092490
Let {{{ a }}} = the age of the father
Let {{{ b }}} = the age of the younger daughter
{{{ 30 }}} = the age of the elder sister
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(1) {{{ a = 2b }}}
(2) {{{ b = 30 - 5 }}}
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(2) {{{ b = 25 }}}
(1) {{{ a = 2*25 }}}
(1) {{{ a = 50 }}}
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The father is 50
The younger daughter is 25