The given number has 6 decimal places.
Now,

i.e. 326 – 2 = 324 Which is a perfect square of 18.
Therefore, 0.000002 should be subtracted from 0.000326 to make it a perfect square of 0.018.

Correct Option: B

The given number has 6 decimal places.
Now,

i.e. 326 – 2 = 324 Which is a perfect square of 18.
Therefore, 0.000002 should be subtracted from 0.000326 to make it a perfect square of 0.018.

Obviously, 16 must be subtracted to make the result a perfect square.
i.e.  63520–16 = √63504 = 252

Correct Option: A

Obviously, 16 must be subtracted to make the result a perfect square.
i.e.  63520–16 = √63504 = 252

1008 = 4 × 4 × 3 × 3 × 7

Correct Option: D

1008 = 4 × 4 × 3 × 3 × 7

Let the numbers be x and y and x > y.
∴  xy = 45
and x – y = 4
∴  x² + y² = (x – y)² + 2xy
= (4)² + 2 × 45 = 16 + 90
= 106

Correct Option: D

Let the numbers be x and y and x > y.
∴  xy = 45
and x – y = 4
∴  x² + y² = (x – y)² + 2xy
= (4)² + 2 × 45 = 16 + 90
= 106

x² + x = 2450
⇒  x (x +1) = 2450 = 49 × 50
∴  x = 49

Correct Option: C

x² + x = 2450
⇒  x (x +1) = 2450 = 49 × 50
∴  x = 49