Question 1013358
Since team A and team B have the same number of students
and ratios won't change whatever the numbers are, I will say:
team A = {{{ 120 }}} students
team B = {{{ 120 }}} students
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team A:
{{{ b/g = 2/1 }}}
{{{ b = 2g }}}
{{{ b = 2*( 120 - b ) }}}
{{{ b = 240 - 2b }}}
{{{ 3b = 240 }}}
{{{ b = 80 }}}
{{{ g = 40 }}}
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team B:
{{{ b/g = 4/11 }}}
{{{ b = (4/11)*g }}}
{{{ b = (4/11)*( 120 - b ) }}}
{{{ b = 43.636 - .3636b }}}
{{{ 1.3636b = 43.636 }}}
{{{ b = 32 }}}
and
{{{ g = 88 }}}
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Total number of boys is:
{{{ 80 + 32 = 112 }}}
Total number of girls is:
{{{ 40 + 88 = 128 }}}
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{{{ b/g = 112/128 }}}
Divide top and bottom by {{{ 16 }}}
{{{ b/g = 7/8 }}}
The ratio of boys to girls in grade 6 is 7/8
check:
{{{ 112/240 = 7/15 }}}
and
{{{ 128/240 = 8/15 }}}
and
{{{ (( 7/15 )) / (( 8/15 )) = 7/8 }}}
OK