Question

cum rezolv:
Problema 1  Daca micsoram de 4 ori a cincea parte dintr-un numar, rezultatul il marim de 10 ori si-l micsoram cu 10, obtinem 60. Determinati numarul.

Problema 2  Daca elevii unei clase ar fi asezati cate 2 in banca ar ramane 3 banci libere, iar daca ar fi asezati cate 3 elevi in banca ar ramane 8 banci libere. Cati elevi si cate banci sunt in clasa ?

Answer 1

1.   [ x/5)/4 ] · 10 -10=60
(x/20  ) ·10=70
x/2=70
x=70 ·2=140

2. x/2 + 3 = x/3+8
   3x+18=2x+48
x=30 elevi
x/2+3=30/2+3=18 banci

Answer 2

[(x:5):4]x 10-10=60
[5/5x1/4]x10-10=60
x/20x10-10=60
x-20=120
x=140
verificare:[(140:5):4]x10-10=60
(28:4)x10-10=60
7x10-10=60