A merchant has 120 litres of oil of one kind, 180 litres of another kind and 240 litres of third kind. He wants to sell the oil by filling the three kinds of oil in tins of equal capacity. What should be the greatest capacity of such a tin?

Explanation

To find the greatest capacity of the tin that the merchant can use to sell the three kinds of oil, we need to determine the highest common factor (HCF) of the quantities of oil he has. The quantities are 120 litres, 180 litres, and 240 litres.

### Step-by-Step Solution:

1. **List the quantities of oil:**
- First kind: 120 litres
- Second kind: 180 litres
- Third kind: 240 litres
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