Question 1011255
Let the present ages of the sisters be
{{{ a }}}, {{{ b }}}, and {{{ c }}}
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(1) {{{ a + b + c = 62 }}}
(2) {{{ a = b + 5 }}}
(3) {{{ b = (1/4)*c }}}
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There are 3 unknowns and 3 equations
so this is solvable
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(3) {{{ c = 4b }}}
Substitute (2) and (3) into (1)
(1) {{{ b + 5 + b + 4b = 62 }}}
(1) {{{ 6b + 5 = 62 }}}
(1) {{{ 6b = 57 }}}
(1) {{{ b = 9.5  }}}
and
(3) {{{ c = 4b }}}
(3) {{{ c = 4*9.5 }}}
(3) {{{ c = 38 }}}
and
(2) {{{ a = b + 5 }}}
(2) {{{ a =9.5 + 5 }}}
(2) {{{ a = 14.5 }}}
Their ages are: 9.5, 14.5, and 38
check:
(1) {{{ a + b + c = 62 }}}
(1) {{{ 14.5 + 9.5 + 38 = 62 }}}
(1) {{{ 62 = 62 }}}
OK