Answer:
13
Step-by-step explanation:
there is a rule that says that if you add any 2 sides, it should be more than the third. 9+21 is greater than 13. 21+13 is greater than 9. 13 is the only number which if you add 9 to it it will be greater than 21. 12 will equal 21, but it still wont work.
hope this helps :))
Answer:
13
Step-by-step explanation:
Given:
- Square stickers that were 3/4 in long
- The spine is 10 and 1/2 in long
If she laid the stickers side by side without gaps or overlaps so the number of sticker to cover the length of the spine:

10 :
≈13
She needs 13 stickers cover the length of the spine
6x+15-4
6x+11
Hope this helps
5 times 2/6 is 10/6
You can simplify that to 5/3