Hi there!
To find the unknown addend, we can just subtract:
1 - 2/6 = 4/6
4/6 = 2/3
Hope this helps!
I believe b equals 5, which would make 2x5 +5, making it 15.
This is pretty hard but um in decimal form it would make 0.9010162353515625, but to simplify it the answer would be 0.9
2 6/7 ÷ 2/3
= 20/7 ÷ 2/3
20/7 × 3/2
= 60/14
reduce to it's lowest term
30/7 = 4 2/7
