Add Four Two-Digit Numbers - 2nd Grade Math

1. What is $49 + 26 + 14 + 11$?

   $100$. Group: $(49+11)+(26+14)=60+40=100$.

2. What is $56 + 23 + 11$?

   $90$. Regroup: $(56+11)+(23)=67+23=90$.

3. What is $38 + 12 + 22 + 28$ (group to make $50$ or $60$)?

   $100$. $38 + 22 = 60$ and $12 + 28 = 40$, so $60 + 40 = 100$.

4. Identify the property shown: $(20 + 5) + 13 = 20 + (5 + 13)$.

   Associative property of addition. Grouping changes but sum stays the same.

5. What is $11 + 22 + 33 + 44$ (add in any order)?

   $110$. $11 + 44 = 55$ and $22 + 33 = 55$, so $55 + 55 = 110$.

6. What is $27 + 38 + 43$ (add tens and ones)?

   $108$. Tens: $20 + 30 + 40 = 90$, ones: $7 + 8 + 3 = 18$, so $90 + 18 = 108$.

7. What is $32 + 46 + 18$ (add tens first, then ones)?

   $96$. Tens: $30 + 40 + 10 = 80$, ones: $2 + 6 + 8 = 16$, so $80 + 16 = 96$.

8. What is $38 + 24 + 12 + 16$?

   $90$. Group pairs: $(38+12)+(24+16)=50+40=90$.

9. Identify the property shown: $18 + 32 = 32 + 18$.

   Commutative property of addition. Order of addends can be switched without changing the sum.

10. What is $39 + 21 + 17 + 13$?

    $90$. Group: $(39+21)+(17+13)=60+30=90$.

11. What is $48 + 35$ using place value (add tens, then ones)?

    $83$. Add tens: $40 + 30 = 70$, then ones: $8 + 5 = 13$, so $70 + 13 = 83$.

12. What is $48 + 12 + 30$?

    $90$. Group for easier addition: $(48+12)+(30)=60+30=90$.

13. What is $45 + 15 + 22 + 18$?

    $100$. Group: $(45+15)+(22+18)=60+40=100$.

14. What is $58 + 27 + 13$ (make a ten with $27$ and $13$)?

    $98$. $27 + 13 = 40$, then $58 + 40 = 98$.

15. What is $26 + 24 + 25 + 25$?

    $100$. Add pairs: $(26+24)+(25+25)=50+50=100$.

16. What is $16 + 28 + 34 + 12$?

    $90$. Pair: $(16+34)+(28+12)=50+40=90$.

17. What is $34 + 25 + 16$?

    $75$. Add the ones place first: $4+5+6=15$, carry 1; then tens: $3+2+1+1=7$.

18. What is $40 + 26 + 30 + 14$ (use tens and ones)?

    $110$. Tens: $40 + 30 = 70$, ones: $26 + 14 = 40$, so $70 + 40 = 110$.

19. What is $14 + 26 + 36 + 24$ (pair numbers to make tens)?

    $100$. $14 + 36 = 50$ and $26 + 24 = 50$, so $50 + 50 = 100$.

20. What is $45 + 19 + 15$ (use compensation for $19$)?

    $79$. $45 + 20 - 1 + 15 = 79$ (add 20 instead of 19, then subtract 1).

21. What is $72 + 19 + 9$ (use compensation and make a ten)?

    $100$. $72 + 20 - 1 + 9 = 100$ (use 20 for 19, then adjust).

22. What is $59 + 41 + 12$ (look for a pair that makes $100$)?

    $112$. $59 + 41 = 100$, then $100 + 12 = 112$.

23. What is the value of $3$ tens and $7$ ones written as a number?

    $37$. 3 tens = 30, plus 7 ones = 37.

24. What is $33 + 17 + 28 + 12$?

    $90$. Pair: $(33+17)+(28+12)=50+40=90$.

25. What is $27 + 19 + 33 + 11$?

    $90$. Pair compatible numbers: $(27+33)+(19+11)=60+30=90$.

26. What is $29 + 31 + 20$?

    $80$. Combine: $(29+31)+(20)=60+20=80$.

27. What is $19 + 27 + 14$?

    $60$. Add ones: $9+7+4=20$, carry 2; add tens: $1+2+1+2=6$.

28. What is $24 + 39 + 16 + 21$ (group to make $40$ and $60$)?

    $100$. $24 + 16 = 40$ and $39 + 21 = 60$, so $40 + 60 = 100$.

29. What is $22 + 35 + 18$?

    $75$. Add ones: $2+5+8=15$, carry 1; add tens: $2+3+1+1=7$.

30. What is $65 + 14 + 21$?

    $100$. Reorder: $(65+21)+(14)=86+14=100$.

31. What is $15 + 35 + 55$ (add in any order)?

    $105$. $15 + 35 = 50$, then $50 + 55 = 105$.

32. What is $40 + 27 + 33$?

    $100$. Group compatible numbers: $(40+33)+(27)=73+27=100$.

33. What is $11 + 22 + 33 + 44$?

    $110$. Pattern: $11+22+33+44=(11+44)+(22+33)=55+55=110$.

34. What is $67 + 18$ (add $20$ then subtract $2$)?

    $85$. $67 + 20 - 2 = 85$ (add 20, then subtract 2).

35. What is $29 + 17$ (make a new ten if needed)?

    $46$. $9 + 7 = 16$, carry 1 ten; $20 + 10 + 10 = 40$, plus 6 ones = 46.

36. What is $25 + 25 + 25 + 25$ (use repeated addition)?

    $100$. Four 25s make 100 (like 4 quarters = $1).

37. What is $33 + 28 + 47$ (add in any order)?

    $108$. $33 + 47 = 80$, then $80 + 28 = 108$.

38. What is $36 + 48 + 14$ (make a ten with $36$ and $14$)?

    $98$. $36 + 14 = 50$, then $50 + 48 = 98$.

39. What is $16 + 27 + 34$ (add in any order)?

    $77$. $16 + 34 = 50$, then $50 + 27 = 77$.

40. What is $52 + 13 + 25 + 10$?

    $100$. Combine: $(52+13)+(25+10)=65+35=100$.

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