Cine ma ajuta cu aceste exercitii? 7, 8, 9, 10.

7 .40-(20:4+20)=40-(5+20)=40-25=15
8. 1850+550=2400
1850+2400=4250
9. 36:4=9
9×2=18
18+9=27
36-27=9
10. 28-10=18
18:2=9