Question

What are the binary representation of the following decimal numbers? 18,27,42

Answer 1

Expand in the new basis!

18=16+218=16+2

=1∗24+0∗23+0∗22+1∗21+0∗20=1∗24+0∗23+0∗22+1∗21+0∗20

→10010→10010

27=16+8+2+127=16+8+2+1

=1∗24+1∗23+0∗22+1∗21+1∗20=1∗24+1∗23+0∗22+1∗21+1∗20

→11011→11011

42=32+8+242=32+8+2

=1∗25+0∗24+1∗23+0∗22+1∗21+0∗20=1∗25+0∗24+1∗23+0∗22+1∗21+0∗20

→101010

Answer 2

18 => xviii

27 => xxvii

42 => xLii
Hope it will help