Correct Answer - Option 4 : 80

**Given:**

When 65% of the number is subtracted from itself, the result becomes square root of 784

**Concept Used:**

Concept of percentage. It is calculated on the basis of 100.

For example, x% means x out of 100

**Calculation:**

Let, the number be x

65% of x = 65x/100 = 0.65x

Accordingly,

x – 0.65x = √784

⇒ 0.35x = 28

⇒ x = 28/0.35

⇒ x = (28 × 100)/35 = 80

**∴ The required number is 80.**