Question 884150
Let {{{ m }}} = the man's age now
Let {{{ d }}} = daughter's age now
Let {{{ s }}} = son's age now
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(1) {{{ s = d + 3 }}}
(2) {{{ m + 1 = 6d }}}
(3) {{{ m + 10 = d + 10 + s + 10 + 14 }}}
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(2) {{{ m = 6d - 1 }}}
(3) {{{ m - d - s = 24 }}}
Substitute (1) and (2) into (3) 
(3) {{{ 6d - 1 - d - d - 3 = 24 }}}
(3) {{{ 4d = 28 }}}
(3) {{{ d = 7 }}}
and
(1) {{{ s = d + 3 }}}
(1) {{{ s = 7 + 3 }}}
(1) {{{ s = 10 }}}
and
(2) {{{ m = 6d - 1 }}}
(2) {{{ m = 6*7 - 1 }}}
(2) {{{ m = 41 }}}
The man is 41
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check:
The son is 3 yrs older than daughter -check
In 1 yr, man is 42, 6 times older than daughter -check
In 10 yrs, man is 51
Son and daughter will be 20 and 17
20 + 17 + 14 = 51 -check