Question 452838
The ratio of boys to girls is {{{ 3/4 }}}
Let {{{b}}} = number of boys
Let {{{g}}} = number of girls
given:
(1) {{{ b + g = 140 }}}
(2) {{{ b/g = 3/4 }}}
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(2) {{{ b = (3/4)*g }}}
Substitute this into (1)
(1) {{{ (3/4)*g + g = 140 }}}
(1) {{{ 3g + 4g = 560 }}}
(1) {{{ 7g = 560 }}}
(1) {{{ g = 80 }}}
and
(1) {{{ b + 80 = 140 }}}
(1) {{{ b = 60 }}}
There are 60 boys and 80 girls