Answers

2014-10-15T15:27:56+08:00
there are 42 boys present and 1 boy absent (43 boys in all)

I subtract the number of absentee/s     ===>  
64-1=63
then divide it to 3 cause "twice more boys than girls". ==> 63 ÷ 3 = 21
Multiply 21 to 2      ====> 21× 2 = 42
21+42=63 (plus one for the absent cause it says "64 kids enrolled in a class."
so ....
42 are boys, while there are 21 girls.
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