Equivalent ratios: word problems
Key Notes :
1. Understanding Equivalent Ratios
- Two ratios are considered equivalent if they represent the same relationship between the two quantities.
- Equivalent ratios can be found by multiplying or dividing both terms of a ratio by the same non-zero number.
Example:
- Ratio 1: 4:6
- Ratio 2: 8:12
- These are equivalent because both ratios simplify to 2:3.
2. Simplifying Ratios to Find Equivalent Ratios
- To find equivalent ratios, simplify the given ratio by dividing both terms by their greatest common factor (GCF).
- Example:
For the ratio 12:18, the GCF is 6. Divide both terms by 6:

- Therefore, 12:18 is equivalent to 2:3.
3. Multiplying to Find Equivalent Ratios
- Alternatively, you can multiply both terms of a ratio by the same number to generate an equivalent ratio.
- Example: If the ratio is 2:3 and you multiply both parts by 4, you get 8:12, which is equivalent to 2:3.
4. Setting Up Word Problems
- Identify the ratio described in the word problem.
- Set up a proportion if the problem involves finding an unknown value.
- Use the property of equivalent ratios to solve for the unknown.
5. Solving Word Problems
- Step 1: Write the given ratios.
- Step 2: Set up a proportion (an equation where two ratios are equal).
- Step 3: Solve for the unknown variable.
Learn with an example
✈️ Are these ratios equivalent?
✈️ 12 medium rugs to 4 small rugs
✈️ 23 medium rugs to 9 small rugs
- yes
- no
Write the ratios as fractions.
12/4 and 23/9
Compare the two fractions to see if they are equivalent.

12 × 9 = 4 × 23 —–>Multiply both sides by 4 × 9
108 ≠ 92 ——>Simplify
The cross products are not equal, so the ratios are not equivalent.
✈️ Are these ratios equivalent?
✈️ 18 crossword puzzles to 20 word searches
✈️ 9 crossword puzzles to 10-word searches
- yes
- no
Write the ratios as fractions.
18/20 and 9/10
Compare the two fractions to see if they are equivalent.

18 × 10 = 20 × 9 ——->Multiply both sides by 20 × 10
180 = 180 ——>Simplify
The fractions are equivalent, so the ratios are equivalent.
✈️ Are these ratios equivalent?
✈️ 42 teachers: 32 students
✈️ 22 teachers: 19 students
- yes
- no
Write the ratios as fractions.
42 / 32 and 22 / 19
Compare the two fractions to see if they are equivalent.

42 × 19 = 32 × 22 ——>Multiply both sides by 32 × 19
798 ≠ 704 —–>Simplify
The cross-products are not equal, so the ratios are not equivalent.
Let’s practice! 🖊️