Add and Subtract Within 1000 - 2nd Grade Math

1. Which property is shown by $246 + 300 = 300 + 246$?

   Commutative property of addition. Order doesn't matter when adding numbers.

2. What is $805 - 467$?

   $338$. $805 - 467 = 338$ with borrowing from tens and hundreds.

3. What is the value of $5$ hundreds $+\ 12$ tens $+\ 9$ ones?

   $629$. $500 + 120 + 9 = 629$ after regrouping tens.

4. What is $900 - 458$?

   $442$. $900 - 458 = 442$ with borrowing from hundreds and tens.

5. What number makes this true: $600 - \square = 275$?

   $325$. $600 - 275 = 325$, so the missing number is $325$.

6. What is the missing number in $725 - 400 = \square$?

   $325$. $725 - 400 = 325$ by subtracting hundreds place.

7. What is $300 + 40 + 6$ written as a standard number?

   $346$. Combine the hundreds, tens, and ones values.

8. What is the missing number in $538 + \square = 900$?

   $362$. $900 - 538 = 362$ to find the missing addend.

9. Which property is shown by $(120 + 80) + 5 = 120 + (80 + 5)$?

   Associative property of addition. Grouping doesn't change the sum.

10. What is $503 - 176$?

    $327$. Regroup twice: $13-6=7$ ones, $9-7=2$ tens, $4-1=3$ hundreds.

11. What does it mean to subtract by place value in $3$-digit subtraction?

    Subtract hundreds from hundreds, tens from tens, ones from ones. Each place value is subtracted separately without mixing.

12. What property is shown by $(200 + 30) + 5 = 200 + (30 + 5)$?

    Associative property of addition. Grouping doesn't matter when adding multiple numbers.

13. What is the best description of place value adding within $1000$?

    Add ones to ones, tens to tens, and hundreds to hundreds. This follows place value rules for addition.

14. What is the value of the digit $7$ in $472$?

    $70$. The 7 is in the tens place, so it represents $7 \times 10$.

15. What is $900 - 457$?

    $443$. Regroup twice: $10-7=3$ ones, $9-5=4$ tens, $8-4=4$ hundreds.

16. Which property shows $(200 + 30) + 7 = 200 + (30 + 7)$?

    Associative property of addition. Grouping doesn't change the sum when adding three numbers.

17. What is the missing addend in $438 + \square = 700$?

    $262$. $700 - 438 = 262$, so the missing addend is $262$.

18. What is the expanded form of $472$ using hundreds, tens, and ones?

    $400 + 70 + 2$. Shows $4$ hundreds, $7$ tens, and $2$ ones separately.

19. What is $725 - 312$?

    $413$. $5-2=3$ ones, $2-1=1$ tens, $7-3=4$ hundreds.

20. What is $701 - 356$?

    $345$. $701 - 356 = 345$ with borrowing from hundreds.

21. What is $600 - 248$?

    $352$. Regroup: $10-8=2$ ones, $9-4=5$ tens, $5-2=3$ hundreds.

22. What does it mean to decompose a hundred when subtracting within $1000$?

    Trade $1$ hundred for $10$ tens. Borrowing when not enough tens to subtract.

23. What does it mean to compose a hundred when adding within $1000$?

    Trade $10$ tens for $1$ hundred. Regrouping when tens sum to 10 or more.

24. What is the missing number $x$ in $438 + x = 600$?

    $162$. $600-438=162$ because addition and subtraction are inverse operations.

25. What is $596 + 208$?

    $804$. $596 + 208 = 804$ with regrouping ones.

26. What property shows $326 + 145 = 145 + 326$?

    Commutative property of addition. Order doesn't matter when adding two numbers.

27. What does it mean to decompose a ten when subtracting within $1000$?

    Trade $1$ ten for $10$ ones. Borrowing when not enough ones to subtract.

28. What does it mean to compose a ten when adding within $1000$?

    Trade $10$ ones for $1$ ten. Regrouping when ones sum to 10 or more.

29. What is $384 + 215$?

    $599$. $384 + 215 = 599$ by adding place values.

30. What property is shown by $320 + 150 = 150 + 320$?

    Commutative property of addition. Order doesn't matter when adding numbers.

31. What is $742 - 318$?

    $424$. $742 - 318 = 424$ with borrowing from tens.

32. What is the value of $(300 + 40 + 9) - (100 + 20 + 5)$?

    $224$. $349-125=224$ by subtracting each place value.

33. What is $267 + 339$?

    $606$. $7+9=16$ ones (regroup), $6+3+1=10$ tens (regroup), $2+3+1=6$ hundreds.

34. What is $399 + 6$ using compensation (make a hundred)?

    $405$. Add $1$ to make $400$, then add $5$ more: $400 + 5 = 405$.

35. What is the regrouping rule when there are not enough tens to subtract?

    Trade $1$ hundred for $10$ tens. Borrowing from hundreds gives $10$ tens for subtraction.

36. What is the regrouping rule when there are not enough ones to subtract?

    Trade $1$ ten for $10$ ones. Borrowing from tens gives $10$ ones for subtraction.

37. What is $560 - 240$?

    $320$. $560 - 240 = 500 - 200 + 60 - 40 = 320$.

38. What is $703 + 189$?

    $892$. $703 + 189 = 892$ with regrouping ones.

39. What is the missing number $x$ in $x - 189 = 400$?

    $589$. $400+189=589$ because addition undoes the subtraction.

40. What is $275 + 489$?

    $764$. $275 + 489 = 764$ with regrouping ones.

41. In $462 - 178$, what does it mean to regroup $1$ ten as ones?

    Trade $1$ ten for $10$ ones. Break down $1$ ten into $10$ ones for easier subtraction.

42. What is the missing number $x$ in $700 - x = 468$?

    $232$. $700-468=232$ because subtraction finds the difference.

43. What is the regrouping rule when $10$ ones are made during addition?

    Trade $10$ ones for $1$ ten. This follows place value rules where $10$ ones equal $1$ ten.

44. What is $408 + 175$?

    $583$. $8+5=13$ ones (regroup), $0+7+1=8$ tens, $4+1=5$ hundreds.

45. What is $500 - 199$ using compensation (subtract $200$, then adjust)?

    $301$. Subtract $200$ to get $300$, then add back $1$: $301$.

46. What does it mean to add by place value in $3$-digit addition?

    Add hundreds to hundreds, tens to tens, ones to ones. Each place value is added separately without mixing.

47. What is the regrouping rule when $10$ tens are made during addition?

    Trade $10$ tens for $1$ hundred. This follows place value rules where $10$ tens equal $1$ hundred.

48. What is $356 + 142$?

    $498$. $6+2=8$ ones, $5+4=9$ tens, $3+1=4$ hundreds.

49. What is $600 - 275$?

    $325$. $600 - 275 = 325$ with borrowing from hundreds and tens.

50. What is $468 + 357$?

    $825$. $468 + 357 = 825$ with regrouping ones and tens.

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