Question 184574
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Remember number of students:
{{{Girls=G}}}
{{{Boys=2G-3}}}
Condition: {{{B+G=57}}}
Then, {{{2G-3+G=57}}}
{{{3G=57+3=60}}}
{{{cross(3)G/cross(3)=cross(60)20/cross(3)}}}
{{{highlight(G=20)}}}, number of Girls
{{{Boys=2*20-3=40-3=highlight(37)}}}, number of Boys
Check via condition:
{{{37+20=57}}}
{{{57=57}}}
Thank you,
Jojo</pre>