Question 34375
b=.6t b=boys t=total number in class
b+6=.75t substituting .6t for b in the second equation we get
.6t+6=.75t ot 6=.15t or t=6/.15 or t=40 therefore .6*40=boys or .6*40=24 boys and 16 girls (40-24) at the beginning of school.

24+6=30 OR .75*40=30