4. 140,142,144,146,148,240,242,244,246,248,340,342,344,346,348,440,442 etc. toate numerele care se sfarsesc cu 0,2,4,6,8.
5. 2⇔2x2+10=14
6. 2x2x2x2=4x2x2=8x2=16
7. 1,2,7,14
8. 2
1. a x (b+c)=7x21=147
2. 18x5=90
3. a) (6+7+9+10):4=(13+9+10):4=(22+10):4=32:4=8
b) 10:2=5
12-10=2
