Question

12 + 15 = 15 + 12

( 6 + 3 ) + 10 = 6 + (3 + 10 )

3 + 7 = 7 + 3

15 + 0 = 0 + 15​

Answer 1

Resposta:

12+15=27+15+12=54

6+3+10=19+6+13=38

15+15=30