Question

Paul si Mihai au impreuna 4 mere.
Mihai si Calin au impreuna 10 mere.
Paul si Calinau impreuna 12 mere.
Care sunt cele doua nr ?

Answer 1

P+M=4
M+C=10
P+C=12

2× (M+P+C)=4+10+12 [26]
M+P+C= 26:2=13

4+C=13
C=13-4=9

P+10=13
P=13-10=3

M+12=13
M=13-12=1

Answer 2

p+m+m+c+p+c=4+10+12
2p+2m+2c=26
2(p+m+c)=26
p+m+c=13

p+m+c=13
p+m=4=>c=13-4=9 mere
m+c=10=>p=13-10=3 mere
p+c=12=>m=13-12=1 mere