Find the squares of:

(i) 85

(ii) 115

(iii) 165

(i) 85

Since 85 terminates with 5.

⇒ 8 × (8 + 1)

8 × 9 = 72

So, 85² = 7225

(ii) 115

Since 115 terminates with 5.

⇒ 11 × (11 + 1)

11 × 12 = 132

So, 115² = 13225

(iii) 165

Since 165 terminates with 5.

⇒ 16 × (16 + 1)

16 × 17 = 272

So, 165² = 27225