Numbers - General Aptitude

Q1:

5358 x 51 = ?

A 273258

B 273268

C 273348

D 273358

ANS:A - 273258

5358 x 51 = 5358 x (50 + 1)
  = 5358 x 50 + 5358 x 1
  = 267900 + 5358
  = 273258.