Correct Answer - Option 3 : 6 : 8 :: 15 : 24

**Formula Used:**

Product of mean = Product of extreme

**Calculation:**

Option 1:

The product of mean = 20 × 15 = 300

The product of extreme = 25 × 12 = 300

This is satisfied the condition.

Option 2:

The product of mean = 10 × 36 = 360

The product of extreme = 45 × 8 = 360

This is satisfied the condition.

Option 3:

The product of mean = 15 × 8 = 120

The product of extreme = 24 × 6 = 144

This is not satisfied the condition.

**∴ 6 : 8 :: 15 : 24 is not correct proportion.**