1. 7 2/3 + 2 7/12 2. 3/8 x 5/6 3. 4 1/2 x 1 2/3 4. 20 divided by 3 1/2 5. 13 5/9 - 8 1/6 6. 3/4 divided by 7/10 7. 8 1/3 divided by 3 3/4 8. 1 3/5 x 2 5/16 9. 6 1/2 - 1 9/10 10. 2/5 of 40 11. 2 5/8 x 4/7 x 12 12. 4 2/3 divided by 10 answers !

It's just not realistic to present a list of 12 math questions and ask for the answers to all of them at once.  Please post only one question at a time and please share your thoughts about how to solve that question.

I'll focus on one problem:    7 2/3 + 2 7/12

Here the LCD (lowest common denominator) is 12.  7 2/3 becomes 7 8/12.

Add 7 8/12 and 2 7/12:

 7 8/12
+2 7/12

9 15/12                15/12 is not a proper fraction.  Write it as 1 3/12, or 1 1/4.

Then your 9 15/12 becomes (9+1)  1/4, or 10 1/4.