Worksheet for practicing division of unit fractions by whole numbers.

Problem: Dividing Unit Fractions by Whole Numbers

The task involves dividing unit fractions (fractions with a numerator of 1) by whole numbers. The general rule for dividing a fraction by a whole number is:

\[
\frac{a}{b} \div c = \frac{a}{b} \times \frac{1}{c} = \frac{a}{b \cdot c}
\]

Since all the fractions in this problem are unit fractions (\( \frac{1}{n} \)), the formula simplifies to:

\[
\frac{1}{n} \div c = \frac{1}{n \cdot c}
\]

We will apply this rule to each problem step by step.

---

Solutions:

#### 1. \( \frac{1}{4} \div 7 \)
\[
\frac{1}{4} \div 7 = \frac{1}{4 \cdot 7} = \frac{1}{28}
\]

#### 2. \( \frac{1}{5} \div 5 \)
\[
\frac{1}{5} \div 5 = \frac{1}{5 \cdot 5} = \frac{1}{25}
\]

#### 3. \( \frac{1}{6} \div 4 \)
\[
\frac{1}{6} \div 4 = \frac{1}{6 \cdot 4} = \frac{1}{24}
\]

#### 4. \( \frac{1}{8} \div 9 \)
\[
\frac{1}{8} \div 9 = \frac{1}{8 \cdot 9} = \frac{1}{72}
\]

#### 5. \( \frac{1}{9} \div 6 \)
\[
\frac{1}{9} \div 6 = \frac{1}{9 \cdot 6} = \frac{1}{54}
\]

#### 6. \( \frac{1}{14} \div 4 \)
\[
\frac{1}{14} \div 4 = \frac{1}{14 \cdot 4} = \frac{1}{56}
\]

#### 7. \( \frac{1}{7} \div 9 \)
\[
\frac{1}{7} \div 9 = \frac{1}{7 \cdot 9} = \frac{1}{63}
\]

#### 8. \( \frac{1}{3} \div 12 \)
\[
\frac{1}{3} \div 12 = \frac{1}{3 \cdot 12} = \frac{1}{36}
\]

#### 9. \( \frac{1}{6} \div 7 \)
\[
\frac{1}{6} \div 7 = \frac{1}{6 \cdot 7} = \frac{1}{42}
\]

#### 10. \( \frac{1}{3} \div 16 \)
\[
\frac{1}{3} \div 16 = \frac{1}{3 \cdot 16} = \frac{1}{48}
\]

#### 11. \( \frac{1}{9} \div 9 \)
\[
\frac{1}{9} \div 9 = \frac{1}{9 \cdot 9} = \frac{1}{81}
\]

#### 12. \( \frac{1}{16} \div 5 \)
\[
\frac{1}{16} \div 5 = \frac{1}{16 \cdot 5} = \frac{1}{80}
\]

#### 13. \( \frac{1}{12} \div 5 \)
\[
\frac{1}{12} \div 5 = \frac{1}{12 \cdot 5} = \frac{1}{60}
\]

#### 14. \( \frac{1}{18} \div 4 \)
\[
\frac{1}{18} \div 4 = \frac{1}{18 \cdot 4} = \frac{1}{72}
\]

#### 15. \( \frac{1}{20} \div 4 \)
\[
\frac{1}{20} \div 4 = \frac{1}{20 \cdot 4} = \frac{1}{80}
\]

#### 16. \( \frac{1}{17} \div 2 \)
\[
\frac{1}{17} \div 2 = \frac{1}{17 \cdot 2} = \frac{1}{34}
\]

#### 17. \( \frac{1}{15} \div 6 \)
\[
\frac{1}{15} \div 6 = \frac{1}{15 \cdot 6} = \frac{1}{90}
\]

#### 18. \( \frac{1}{13} \div 2 \)
\[
\frac{1}{13} \div 2 = \frac{1}{13 \cdot 2} = \frac{1}{26}
\]

#### 19. \( \frac{1}{11} \div 2 \)
\[
\frac{1}{11} \div 2 = \frac{1}{11 \cdot 2} = \frac{1}{22}
\]

#### 20. \( \frac{1}{4} \div 17 \)
\[
\frac{1}{4} \div 17 = \frac{1}{4 \cdot 17} = \frac{1}{68}
\]

---

Final Answers:

\[
\boxed{
\begin{aligned}
1. & \ \frac{1}{28} \\
2. & \ \frac{1}{25} \\
3. & \ \frac{1}{24} \\
4. & \ \frac{1}{72} \\
5. & \ \frac{1}{54} \\
6. & \ \frac{1}{56} \\
7. & \ \frac{1}{63} \\
8. & \ \frac{1}{36} \\
9. & \ \frac{1}{42} \\
10. & \ \frac{1}{48} \\
11. & \ \frac{1}{81} \\
12. & \ \frac{1}{80} \\
13. & \ \frac{1}{60} \\
14. & \ \frac{1}{72} \\
15. & \ \frac{1}{80} \\
16. & \ \frac{1}{34} \\
17. & \ \frac{1}{90} \\
18. & \ \frac{1}{26} \\
19. & \ \frac{1}{22} \\
20. & \ \frac{1}{68}
\end{aligned}
}
\]