Ratio & Proportion

Quantitative Aptitude - Ratio & Proportion

Use ratios for part-to-part and part-to-whole comparisons and proportions.

1. Ratios

Ratio a:b = a/b. Compare quantities directly.

2. Proportions

a:b = c:d implies ad = bc. Solve for unknowns quickly.

3. Applications

• Sharing amounts in given ratios: Add parts and divide.
• Converting ratio to percent: a:b = (a/(a+b)) × 100.

4. Quick Tips

• Simplify both terms before solving proportion.
• Use cross-product to verify or find missing term.

5. Common Errors

• Mixing ratio and percent without conversion.
• Forgetting to simplify ratio before using.

6. Revision Checklist

• Be fluent with a:b, b:c split across multiple groups.
• Practice reverse problems (given whole and part find ratio).

Summary: Ratios compare quantities, proportions set equality; simplify early, use cross-multiplication, and convert to percent or share problems as needed.