Worked examples
Two examples
Example 1
The table shows equal ratios. What number goes where the ? is?
| Cups of rice | 2 | 6 | ? |
|---|---|---|---|
| Cups of water | 3 | 9 | 15 |
- The first column is 2 : 3. In the last column, 15 is 3 × 5.
- Multiply the other number by 5 too: 2 × 5 = 10.
Answer: 10
Example 2
The table shows equal ratios. What number goes where the ? is?
| Tickets | 1 | 4 | 7 |
|---|---|---|---|
| Cost in dollars | 12 | 48 | ? |
- The first column is 1 : 12. In the last column, 7 is 1 × 7.
- Multiply the other number by 7 too: 12 × 7 = 84.
Answer: 84
Where this is taught: Ratio, Proportion, and Percent, “A ratio table”
The drill
Ten problems
This drill also has challenge problems. They use the same skill, set up the way the GED test sometimes sets up a problem, so that it looks new at first.
How many:
Type each answer, then press Check my answers at the bottom. Commas in large numbers are fine.Write each answer on the line. The answer key, with the reasoning, is on the last page.