DUE TOMRROW IF NASWERED PROPERLY ILL GIVE BRAINIEST AND 50 POINTS IN ANEW QUESTION ONLY ANSwERED PROPERLY

Answer:
11. a. yes b. no
12. i. yes ii. yes
13. a. 31/35 b. 1 5/9 c. 1/30 d. 1/15
Step-by-step explanation:
11. add them
12. estimate
13. add or subtract