Add and subtract word problems within 100

Read the story. Decide whether to add or subtract, then solve.

1. Kai has 31 stamps. Kai gets 12 more. How many stamps does Kai have now?
2. Lia has 20 books. Lia gets 21 more. How many books does Lia have now?
3. Kai has 32 buttons. Kai gets 10 more. How many buttons does Kai have now?
4. Mo has 11 stickers. Mo gets 22 more. How many stickers does Mo have now?
5. Jon has 51 crayons. Jon gives away 28. How many crayons does Jon have left?
6. Pia has 72 crayons. Pia gives away 48. How many crayons does Pia have left?
7. Pia has 31 shells. Pia gives away 17. How many shells does Pia have left?
8. Kai has 40 crayons. Kai gives away 35. How many crayons does Kai have left?
9. Ana has 10 cards. Pia has 40 cards. How many cards do they have in all?
10. Chen has 15 pencils. Omar has 30 pencils. How many pencils do they have in all?
11. Kai has 31 cards. Dara has 14 cards. How many cards do they have in all?
12. Kai has 36 buttons. Ana has 13 buttons. How many buttons do they have in all?
13. Eli has 43 crayons. Dara has 39 crayons. How many more crayons does Eli have than Dara?
14. Dara has 98 pencils. Hana has 84 pencils. How many more pencils does Dara have than Hana?
15. Dara has 74 stamps. Omar has 33 stamps. How many more stamps does Dara have than Omar?
16. Lia has 96 books. Kai has 75 books. How many more books does Lia have than Kai?
17. Jon has 47 stamps. Jon gets some more. Now Jon has 82. How many did Jon get?
18. Ana has 66 books. Ana gets some more. Now Ana has 89. How many did Ana get?
19. Gus has 72 stamps. Gus gets some more. Now Gus has 85. How many did Gus get?
20. Ana has 39 blocks. Ana gets some more. Now Ana has 50. How many did Ana get?