A rectangular courtyard 3.78 m lang and 5.25 m broad is to be paved exactly with square tiles, all of the same size. The minimum number of such tiles is:	Choose the correct choice from the following answers:	A) 425	B) 430	C) 440	D) 450	E) 460

Rationale: l = 378 cm and b = 525 cm maximum length of a square tile = hcf of ( 378,525 ) = 21 cm number of tiles = ( 378 × 525 ) / ( 21 × 21 ) = ( 18 × 25 ) = 450 answer is d .
Answer: D