Question 1091669
Let {{{ a }}} = Maria's age now
Let {{{ b }}} = Paula's age now
Let {{{ c }}} = Danielle's age now
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(1) {{{ a = b + 3 }}}
(2) {{{ b = 3c }}}
(3) {{{ a + b + c = 59 }}}
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(2) {{{ c = (1/3)*b }}}
Plug (1) and (2) into (3)
(3) {{{ b + 3 + b + (1/3)*b = 59 }}}
(3) {{{ 2b + (1/3)*b = 56 }}}
Multiply both sides by {{{ 3 }}}
(3) {{{ 6b + b = 168 }}}
(3) {{{ 7b = 168 }}}
(3) {{{ b = 24 }}}
and
(1) {{{ a = 24 + 3 }}}
(1) {{{ a = 27 }}}
and
(2) {{{ c = (1/3)*24 }}}
(2) {{{ c = 8 }}}
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{{{ a + 3 = 30 }}}
{{{ b + 3 = 27 }}}
{{{ c + 3 = 11 }}}
In 3 years:
Maria will be 30
Paula will be 27
Danielle will be 11