Question

Aflati numerele a,b,c, stiind ca: a+b=90, b+c=110 si a+c=100.

Answer 1

Adunam toate cele trei relatii :
a+b+b+c+a+c =90 + 110 + 100
2a + 2b + 2c = 90 + 110 + 100
2(a+b+c) = 300
a+b+c = 150
b+c = 110
a + 110 = 150
a = 150 - 110
a = 40
a + b = 90
40 + b = 90
b = 90 - 40
b = 50
a + c = 100
40 + c = 100
c = 100 - 40
c = 60