Divide Unit Fractions by Whole Numbers - 5th Grade Math

1. What is $\frac{1}{12} \div 6$?

   $\frac{1}{72}$. Multiply denominators: $12\times 6=72$.

2. What is $\frac{1}{6} \div 2$?

   $\frac{1}{12}$. Multiply the denominator: $6 \times 2 = 12$.

3. What is $\frac{1}{2} \div 7$?

   $\frac{1}{14}$. Multiply denominators: $2 \times 7=14$.

4. What is $\frac{1}{8} \div 4$?

   $\frac{1}{32}$. Multiply the denominator: $8 \times 4 = 32$.

5. What is $\frac{1}{2} \div 7$?

   $\frac{1}{14}$. Multiply the denominator: $2 \times 7 = 14$.

6. What is $\frac{1}{9} \div 3$?

   $\frac{1}{27}$. Multiply the denominator: $9 \times 3 = 27$.

7. What is $\frac{1}{10} \div 3$?

   $\frac{1}{30}$. Multiply denominators: $10\times 3=30$.

8. What is $\frac{1}{9} \div 2$?

   $\frac{1}{18}$. Multiply denominators: $9\times 2=18$.

9. What is $\frac{1}{16} \div 8$?

   $\frac{1}{128}$. Multiply the denominator: $16 \times 8 = 128$.

10. What is $\frac{1}{13} \div 4$?

    $\frac{1}{52}$. Multiply the denominator: $13 \times 4 = 52$.

11. What is $\frac{1}{16} \div 2$?

    $\frac{1}{32}$. Multiply the denominator: $16 \times 2 = 32$.

12. What is $\frac{1}{7} \div 5$?

    $\frac{1}{35}$. Multiply the denominator: $7 \times 5 = 35$.

13. What is $\frac{1}{7} \div 7$?

    $\frac{1}{49}$. Multiply the denominator: $7 \times 7 = 49$.

14. What is the meaning of $\frac{1}{a} \div n$ in words?

    One $\frac{1}{n}$-sized part of $\frac{1}{a}$. Dividing into $n$ equal parts makes each part $n$ times smaller.

15. What is $\frac{1}{15} \div 5$?

    $\frac{1}{75}$. Multiply the denominator: $15 \times 5 = 75$.

16. What is the missing whole number $a$ in $\frac{1}{9}\div a=\frac{1}{36}$?

    $a=4$. Since $9\times a=36$, $a=4$.

17. What is $\frac{1}{12} \div 3$?

    $\frac{1}{36}$. Multiply the denominator: $12 \times 3 = 36$.

18. What is $\frac{1}{12} \div 6$?

    $\frac{1}{72}$. Multiply the denominator: $12 \times 6 = 72$.

19. What is $\frac{1}{8}\div 4$?

    $\frac{1}{32}$. Multiply denominators: $8\times 4=32$.

20. What is $\frac{1}{6} \div 2$?

    $\frac{1}{12}$. Apply the rule: $\frac{1}{6}\div 2=\frac{1}{6\times 2}=\frac{1}{12}$.

21. What is $\frac{1}{25} \div 5$?

    $\frac{1}{125}$. Multiply the denominator: $25 \times 5 = 125$.

22. What is $\frac{1}{4}\div 3$?

    $\frac{1}{12}$. Multiply denominators: $4\times 3=12$.

23. What is $\frac{1}{3}\div 5$?

    $\frac{1}{15}$. Multiply denominators: $3\times 5=15$.

24. What is $\frac{1}{7}\div 7$?

    $\frac{1}{49}$. Multiply denominators: $7\times 7=49$.

25. What is $\frac{1}{5} \div 9$?

    $\frac{1}{45}$. Multiply denominators: $5\times 9=45$.

26. What is the missing whole number $b$ in $\frac{1}{b}\div 3=\frac{1}{30}$?

    $b=10$. Since $b\times 3=30$, $b=10$.

27. What is $\frac{1}{5} \div 3$?

    $\frac{1}{15}$. Multiply the denominator: $5 \times 3 = 15$.

28. What is the rule for dividing a unit fraction by a whole number $n$?

    $\frac{1}{a} \div n = \frac{1}{a \times n}$. Multiply the denominator by the whole number.

29. What is $\frac{1}{18} \div 3$?

    $\frac{1}{54}$. Multiply the denominator: $18 \times 3 = 54$.

30. Which expression is equivalent to $\frac{1}{a} \div n$: $\frac{1}{a \cdot n}$ or $\frac{n}{a}$?

    $\frac{1}{a \cdot n}$. Division multiplies the denominator, not the numerator.

31. What is $\frac{1}{15} \div 3$?

    $\frac{1}{45}$. Multiply the denominator: $15 \times 3 = 45$.

32. What is $\frac{1}{11}\div 2$?

    $\frac{1}{22}$. Multiply denominators: $11\times 2=22$.

33. What is $\frac{1}{11} \div 2$?

    $\frac{1}{22}$. Multiply the denominator: $11 \times 2 = 22$.

34. What is $\frac{1}{2} \div 9$?

    $\frac{1}{18}$. Multiply the denominator: $2 \times 9 = 18$.

35. What is $\frac{1}{20} \div 4$?

    $\frac{1}{80}$. Multiply the denominator: $20 \times 4 = 80$.

36. Identify the correct simplification: $\frac{1}{6} \div 4$ equals $\frac{1}{24}$ or $\frac{4}{6}$?

    $\frac{1}{24}$. Apply the rule: $6\times 4=24$.

37. Which expression is equivalent to $\frac{1}{b} \div a$: $\frac{1}{b} \times a$ or $\frac{1}{b} \times \frac{1}{a}$?

    $\frac{1}{b} \times \frac{1}{a}$. Dividing by $a$ equals multiplying by $\frac{1}{a}$

38. What does $\frac{1}{b} \div a$ mean in words when $a$ is a non-zero whole number?

    It means splitting $\frac{1}{b}$ into $a$ equal parts. Each part is $\frac{1}{a}$ of the original unit fraction.

39. What is the missing number $n$ in $\frac{1}{n}=\frac{1}{8}\div 5$?

    $n=40$. Since $\frac{1}{8}\div 5=\frac{1}{40}$, $n=40$.

40. What is the rule for computing $\frac{1}{b} \div a$ for non-zero whole numbers $a$ and $b$?

    $\frac{1}{b}\div a=\frac{1}{ab}$. Dividing by $a$ multiplies the denominator by $a$.

41. Identify the missing number: $\frac{1}{9} \div 4 = \frac{1}{\square}$.

    $36$. Multiply the denominator: $9 \times 4 = 36$.

42. What is $\frac{1}{10} \div 5$?

    $\frac{1}{50}$. Multiply the denominator: $10 \times 5 = 50$.

43. What is the missing number $n$ in $\frac{1}{6}\div 2=\frac{1}{n}$?

    $n=12$. Since $\frac{1}{6}\div 2=\frac{1}{12}$, $n=12$.

44. What is $\frac{1}{3} \div 8$?

    $\frac{1}{24}$. Multiply the denominator: $3 \times 8 = 24$.

45. Find and correct the error: $\frac{1}{6} \div 3 = \frac{1}{2}$.

    Correct: $\frac{1}{6} \div 3 = \frac{1}{18}$. The error was dividing instead of multiplying the denominator.

46. What is $\frac{1}{4} \div 6$?

    $\frac{1}{24}$. Multiply the denominator: $4 \times 6 = 24$.

47. What is $\frac{1}{4} \div 2$?

    $\frac{1}{8}$. Multiply the denominator: $4 \times 2 = 8$.

48. What is $\frac{1}{25} \div 2$?

    $\frac{1}{50}$. Multiply the denominator: $25 \times 2 = 50$.

49. What is $\frac{1}{3} \div 7$?

    $\frac{1}{21}$. Multiply the denominator: $3 \times 7 = 21$.

50. What is $\frac{1}{16}\div 8$?

    $\frac{1}{128}$. Multiply denominators: $16\times 8=128$.

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