A rectangular courtyard 3.78 metres long and 2.25 metres wide is to be paved exactly with square title, all of the same size. What is the largest size of the tile which could be used for the purpose ?	Choose the correct choice from the following
A) 11 cms B) 21 cms C) 42 cms D) None of these E) 46 cms
Solution   Largest size of the tile = H.C.F. of 378 cm an= 21 cm = 525 cm. Answer 21 cms
<result>B</result>
A rectangular courtyard 3.78 metres long and 2.25 metres wide is to be paved exactly with square title, all of the same size. What is the largest size of the tile which could be used for the purpose ?