Răspunsuri

2014-04-26T12:50:29+03:00
B/f=3/4
b=3f/4
b+5=f
3f/4 +5=f  aducem la acelasi numitor
3f+20=4f
3f-4f=-20
-f=-20
f=20
b=3*20/4= 3*5=15
20+15=35 elevi sunt in clasa