Question

Va rog mult,problemele 10,11,13.Urgent!

Answer 1

10) a+b=115
a=2/3xb
2b/3+b=115
2b+3b=115x3
5b=345
b=345:5
b=69
a=2x69/3
a=138/3
a=46

11) a-b=36
a=7/4xb
7b/4-b=36
7b-4b=36x4
3b=144
b=144:3
b=48
a=7x48/4
a=336/4
a=84

13) Ma=(a+b):2=30
a=2/3xb
a=2b/3

2b/3+b=60
2b+3b=60x3
5b=180
b=180:5
b=36
a=2x36/3
a=72/3
a=24