SSC CGL learners · 7 min

Ratio and proportion

Compare quantities with ratios and use equivalent ratios to find unknown values.

Learning objective

Simplify a ratio and solve a direct proportion using equivalent ratios.

A ratio compares quantities by division. Convert both quantities to the same unit before simplifying.

Example

2 metres : 50 centimetres = 200 : 50 = 4 : 1

Divide every part of the ratio by the same common factor. The comparison stays equivalent.

Example

18 : 24 = 3 : 4 (divide both parts by 6)

When two quantities scale together, multiply or divide both by the same factor.

Example

If 3 notebooks cost ₹60, then 5 cost 60 × 5/3 = ₹100.

Knowledge check

A recipe uses 2 cups of rice for 3 people. How many cups are needed for 9 people?4 cups5 cups6 cups9 cups

Your answer stays on this device.

About this lesson

Source: Original GyanStudio learning material. Editorial review pending. Last updated 5 November 2026.

This learning preview is not an official exam notice or a substitute for checking the relevant authority’s current information.