Study the given pattern carefully and select the number that represents the value of x.

36	25	16	9	4
361	x	289	256	225

Given: 

First row: 36, 25, 16, 9, 4
→ These are squares of 6, 5, 4, 3, 2 (decreasing by 1).

Second row: 361, x, 289, 256, 225
→ 361 = 19², 289 = 17², 256 = 16², 225 = 15².
Roots are 19, ?, 17, 16, 15 (also decreasing by 1).

So between 19 and 17, it must be 18.

18² = 324.

So , x = 324.

Thus, correct option is (b).