Question

In a 1 Kg mixture of sand and Iron, 20% is Iron. How much sand should be added, so that the proportion of Iron becomes 5%?

• A. 2.8 Kg
• B. 800 g
• C. 3 Kg
• D. 3.2 Kg

Answer 1

The correct option is C 3 Kg

Ratio of Iron: sand = 1: 4
Required ratio of Iron and Sand = 1: 19
15 parts of sand should be added. 1 part corresponds to 200 g. So, we should add $15\times 200=3$ Kg of sand.