## Question

**Answer :** D

**Solution:**

The two ends of each line contain a number and its square -5.

e.g. 15^{2}-5=220,

18^{2}-5=319,

12^{2}-5 = 139

So, missing number =3^{2}-5 = 4.

So, the answer is **4.**

**Answer :** D

**Solution:**

The two ends of each line contain a number and its square -5.

e.g. 15^{2}-5=220,

18^{2}-5=319,

12^{2}-5 = 139

So, missing number =3^{2}-5 = 4.

So, the answer is **4.**