Question 712163
4+5=9 WHICH REPRESENTS ONE GROUP OF STUDENTS.
1620/9=180 TOTAL GROUPS OF STUDENTS
THERE ARE 4 BOYS IN EACH GROUP.
4*180=720 TOTAL BOYS.
THERE ARE 5 GIRLS IN EACH GROUP.
5*180=900 TOTAL GIRLS.
PROOF:
720+900=1620
1620=1620
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HOPE THIS IS AN ADEQUATE SOLUTION METHOD.