Correct Answer - Option 4 : 35 kg

**Given:**

Ratio of copper and zinc = 13 : 7

**Calculation:**

Let total units is 20 kg

So, in 20 kg of brass zinc will be 7 kg and copper is 13 kg

In 100 kg of brass zinc will be

⇒ 100 × (7/20)

⇒ 35 kg

**∴**** The zinc in 100 kg of brass is 35 kg. **