Understand Division as Missing Factor - 3rd Grade Math

1. Identify the missing factor: $\square \times 8 = 72$.

   $9$. Since $9 \times 8 = 72$, the missing factor is $9$.

2. What number makes the equation $9 \times \square = 63$ true?

   $7$. Since $9 \times 7 = 63$, the missing factor is $7$.

3. What is the missing factor in $45 \div 9 = \square$ if $9 \times \square = 45$?

   $5$. Since $9 \times 5 = 45$, the missing factor is $5$.

4. What is $24 \div 3$ using the unknown-factor equation $3 \times \square = 24$?

   $8$. Division asks what times $3$ equals $24$, which is $8$.

5. Identify the missing number that makes this true: $\square \times 9 = 72$.

   $8$. To find the missing factor, divide $72$ by $9$.

6. What number makes the equation $4 \times \square = 28$ true?

   $7$. Since $4 \times 7 = 28$, the missing factor is $7$.

7. What is $81 \div 9$ using $9 \times \square = 81$?

   $9$. Since $9 \times 9 = 81$, the missing factor is $9$.

8. What number makes $5 \times \square = 35$ true?

   $7$. Since $5 \times 7 = 35$, the missing factor is $7$.

9. What is the missing factor in $63 \div 9 = \square$ if $9 \times \square = 63$?

   $7$. Since $9 \times 7 = 63$, the missing factor is $7$.

10. What is $35 \div 5$ using the unknown-factor equation $5 \times \square = 35$?

    $7$. Division finds the missing factor: $5 \times 7 = 35$.

11. Which division equation matches the multiplication equation $6 \times 7 = 42$ (use the other factor)?

    $42 \div 7 = 6$. Dividing by the other factor gives the first factor.

12. What number makes the equation $6 \times \square = 42$ true?

    $7$. Since $6 \times 7 = 42$, the missing factor is $7$.

13. What does $a \div b$ ask you to find when you think of division as an unknown factor?

    The number $c$ such that $b \times c = a$. Find what times $b$ gives $a$.

14. What is $72 \div 8$ if you rewrite it as $8 \times \square = 72$?

    $9$. Division asks what times $8$ equals $72$, which is $9$.

15. What is $56 \div 7$ using the unknown-factor equation $7 \times \square = 56$?

    $8$. Division asks what times $7$ equals $56$, which is $8$.

16. What is the missing factor in $48 \div 6 = \square$ if $6 \times \square = 48$?

    $8$. Since $6 \times 8 = 48$, the missing factor is $8$.

17. What is $48 \div 6$ if you solve $6 \times \square = 48$?

    $8$. Since $6 \times 8 = 48$, the missing factor is $8$.

18. What is the missing factor in $32 \div 8 = \square$ if $8 \times \square = 32$?

    $4$. Since $8 \times 4 = 32$, the missing factor is $4$.

19. What is $28 \div 4$ using the unknown-factor idea $4 \times \square = 28$?

    $7$. Division finds the missing factor: $4 \times 7 = 28$.

20. What is $48 \div 6$ if you rewrite it as $6 \times \square = 48$?

    $8$. Division asks what times $6$ equals $48$, which is $8$.

21. What does $a \div b = c$ mean as an unknown-factor multiplication equation?

    $b \times c = a$. Division reverses multiplication, so the factors switch positions.

22. What number makes the equation $7 \times \square = 56$ true?

    $8$. Since $7 \times 8 = 56$, the missing factor is $8$.

23. What is the missing factor in $36 \div 4 = \square$ if $4 \times \square = 36$?

    $9$. Since $4 \times 9 = 36$, the missing factor is $9$.

24. Identify the missing factor: $\square \times 6 = 48$.

    $8$. Since $8 \times 6 = 48$, the missing factor is $8$.

25. What is $72 \div 8$ if you solve $8 \times \square = 72$?

    $9$. Since $8 \times 9 = 72$, the missing factor is $9$.

26. What is the missing factor in $81 \div 9 = \square$ if $9 \times \square = 81$?

    $9$. Since $9 \times 9 = 81$, the missing factor is $9$.

27. What is $45 \div 5$ using the unknown-factor equation $5 \times \square = 45$?

    $9$. Division asks what times $5$ equals $45$, which is $9$.

28. Which division equation matches the multiplication equation $6 \times 7 = 42$?

    $42 \div 6 = 7$. Dividing the product by one factor gives the other factor.

29. Which multiplication equation matches the division equation $45 \div 9 = 5$?

    $9 \times 5 = 45$. Division means $9$ times what equals $45$.

30. What is the missing factor in $42 \div 7 = \square$ if $7 \times \square = 42$?

    $6$. Since $7 \times 6 = 42$, the missing factor is $6$.

31. What multiplication equation matches the division equation $a \div b = c$?

    $b \times c = a$. Division and multiplication are inverse operations.

32. What is $32 \div 8$ if you use the unknown-factor idea $8 \times \square = 32$?

    $4$. Since $8 \times 4 = 32$, the missing factor is $4$.

33. What is the missing factor in $72 \div 8 = \square$ if $8 \times \square = 72$?

    $9$. Since $8 \times 9 = 72$, the missing factor is $9$.

34. What is $49 \div 7$ using the equation $7 \times \square = 49$?

    $7$. Division finds the missing factor: $7 \times 7 = 49$.

35. What is the missing factor in $8 \times \square = 72$?

    $9$. Since $8 \times 9 = 72$, the missing factor is $9$.

36. What is $56 \div 7$ if you solve $7 \times \square = 56$?

    $8$. Since $7 \times 8 = 56$, the missing factor is $8$.

37. What number makes the equation $6 \times \square = 54$ true?

    $9$. Since $6 \times 9 = 54$, the missing factor is $9$.

38. What does $a \div b = c$ mean as an unknown-factor equation using multiplication?

    $b \times c = a$. Division reverses multiplication, so the factors switch positions.

39. What is $42 \div 6$ written as an unknown-factor equation?

    $6 \times \square = 42$. Division as finding what times $6$ equals $42$.

40. What is the missing factor in $7 \times \square = 49$?

    $7$. Since $7 \times 7 = 49$, the missing factor is $7$.

41. What is $32 \div 8$ when you use the unknown-factor idea $8 \times \square = 32$?

    $4$. Division asks what times $8$ equals $32$, which is $4$.

42. What does $a \div b = c$ mean when you think of division as an unknown factor?

    It means $b \times c = a$. Division asks what number times the divisor gives the dividend.

43. What number makes the equation $8 \times \square = 32$ true?

    $4$. Since $8 \times 4 = 32$, the missing factor is $4$.

44. What is the missing factor in $9 \times \square = 63$?

    $7$. Since $9 \times 7 = 63$, the missing factor is $7$.

45. What is $63 \div 9$ using the unknown-factor equation $9 \times \square = 63$?

    $7$. Division finds the missing factor: $9 \times 7 = 63$.

46. What number makes the equation $3 \times \square = 24$ true?

    $8$. Since $3 \times 8 = 24$, the missing factor is $8$.

47. Identify the missing number that makes this true: $7 \times \square = 49$.

    $7$. To find the missing factor, divide $49$ by $7$.

48. What number makes the equation $5 \times \square = 45$ true?

    $9$. Since $5 \times 9 = 45$, the missing factor is $9$.

49. What is the missing factor in $28 \div 7 = \square$ if $7 \times \square = 28$?

    $4$. Since $7 \times 4 = 28$, the missing factor is $4$.

50. What is $28 \div 4$ using the unknown-factor equation $4 \times \square = 28$?

    $7$. Division asks what times $4$ equals $28$, which is $7$.

51. What is $64 \div 8$ if you solve $8 \times \square = 64$?

    $8$. Since $8 \times 8 = 64$, the missing factor is $8$.

52. What is $54 \div 6$ using the unknown-factor equation $6 \times \square = 54$?

    $9$. Division asks what times $6$ equals $54$, which is $9$.

53. What is the missing factor in $54 \div 6 = \square$ if $6 \times \square = 54$?

    $9$. Since $6 \times 9 = 54$, the missing factor is $9$.

54. What is the missing factor in $64 \div 8 = \square$ if $8 \times \square = 64$?

    $8$. Since $8 \times 8 = 64$, the missing factor is $8$.

55. What is the missing factor in $56 \div 7 = \square$ if $7 \times \square = 56$?

    $8$. Since $7 \times 8 = 56$, the missing factor is $8$.

56. What number makes $4 \times \square = 28$ true?

    $7$. Since $4 \times 7 = 28$, the missing factor is $7$.

57. What is the missing factor in $30 \div 5 = \square$ if $5 \times \square = 30$?

    $6$. Since $5 \times 6 = 30$, the missing factor is $6$.

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