Let's solve each equation step by step. We are given proportions (equations with fractions), and we need to find the unknown variable in each case. We'll use
cross-multiplication to solve them.
---
1. $\frac{2}{7} = \frac{x}{15}$
Cross-multiply:
$$
2 \cdot 15 = 7 \cdot x \Rightarrow 30 = 7x
$$
Now divide both sides by 7:
$$
x = \frac{30}{7}
$$
As a mixed number: $4\frac{2}{7}$
✔ Answer: $\boxed{\frac{30}{7}}$ or $\boxed{4\frac{2}{7}}$
---
2. $\frac{2}{p} = \frac{9}{4}$
Cross-multiply:
$$
2 \cdot 4 = 9 \cdot p \Rightarrow 8 = 9p
$$
Divide both sides by 9:
$$
p = \frac{8}{9}
$$
✔ Answer: $\boxed{\frac{8}{9}}$
---
3. $\frac{1}{p} = \frac{6}{16}$
First, simplify $\frac{6}{16} = \frac{3}{8}$
So:
$$
\frac{1}{p} = \frac{3}{8}
$$
Cross-multiply:
$$
1 \cdot 8 = 3 \cdot p \Rightarrow 8 = 3p
$$
Divide by 3:
$$
p = \frac{8}{3}
$$
As a mixed number: $2\frac{2}{3}$
✔ Answer: $\boxed{\frac{8}{3}}$ or $\boxed{2\frac{2}{3}}$
---
4. $\frac{2}{5} = \frac{1}{n}$
Cross-multiply:
$$
2 \cdot n = 5 \cdot 1 \Rightarrow 2n = 5
$$
Divide by 2:
$$
n = \frac{5}{2}
$$
As a mixed number: $2\frac{1}{2}$
✔ Answer: $\boxed{\frac{5}{2}}$ or $\boxed{2\frac{1}{2}}$
---
5. $\frac{y}{8} = \frac{1}{28}$
Cross-multiply:
$$
y \cdot 28 = 8 \cdot 1 \Rightarrow 28y = 8
$$
Divide by 28:
$$
y = \frac{8}{28} = \frac{2}{7}
$$
(Simplified by dividing numerator and denominator by 4)
✔ Answer: $\boxed{\frac{2}{7}}$
---
6. $\frac{20}{9} = \frac{8}{c}$
Cross-multiply:
$$
20 \cdot c = 9 \cdot 8 \Rightarrow 20c = 72
$$
Divide by 20:
$$
c = \frac{72}{20} = \frac{18}{5}
$$
(Simplify by dividing numerator and denominator by 4)
As a mixed number: $3\frac{3}{5}$
✔ Answer: $\boxed{\frac{18}{5}}$ or $\boxed{3\frac{3}{5}}$
---
7. $\frac{1}{7} = \frac{k}{13}$
Cross-multiply:
$$
1 \cdot 13 = 7 \cdot k \Rightarrow 13 = 7k
$$
Divide by 7:
$$
k = \frac{13}{7}
$$
As a mixed number: $1\frac{6}{7}$
✔ Answer: $\boxed{\frac{13}{7}}$ or $\boxed{1\frac{6}{7}}$
---
8. $\frac{5}{k} = \frac{9}{10}$
Cross-multiply:
$$
5 \cdot 10 = 9 \cdot k \Rightarrow 50 = 9k
$$
Divide by 9:
$$
k = \frac{50}{9}
$$
As a mixed number: $5\frac{5}{9}$
✔ Answer: $\boxed{\frac{50}{9}}$ or $\boxed{5\frac{5}{9}}$
---
✔ Final Answers:
1. $x = \boxed{\frac{30}{7}}$ or $4\frac{2}{7}$
2. $p = \boxed{\frac{8}{9}}$
3. $p = \boxed{\frac{8}{3}}$ or $2\frac{2}{3}$
4. $n = \boxed{\frac{5}{2}}$ or $2\frac{1}{2}$
5. $y = \boxed{\frac{2}{7}}$
6. $c = \boxed{\frac{18}{5}}$ or $3\frac{3}{5}$
7. $k = \boxed{\frac{13}{7}}$ or $1\frac{6}{7}$
8. $k = \boxed{\frac{50}{9}}$ or $5\frac{5}{9}$
Let me know if you'd like these formatted as a table or printed out!
Parent Tip: Review the logic above to help your child master the concept of cross multiplication worksheet.