Răspuns :
60/100xa=15
60a/100=15
60a=1500
a=1500:60
a=25 total elevi clasa
ax40/100=25x40:100=1000:100=10 sunt baieti
x-băieți
fete=15
x..................40%
15...............60%
x=15•40/60
x=10
fete=15
x..................40%
15...............60%
x=15•40/60
x=10