document.write( "Question 1119783: How many whole numbers between 99 and 999 contain the digit '1'? \n" ); document.write( "

Algebra.Com's Answer #735391 by ikleyn(52787) $\"\"$ $\"About$

You can put this solution on YOUR website!
.
\n" ); document.write( "

\r\n" );
document.write( "One hundred numbers from 100 to 199  having '1' in the hundreds position\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "plus  8*10 = 80  other numbers from 210 to 919 of the table \r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "    210    310   .   910\r\n" );
document.write( "    211    311   .   911\r\n" );
document.write( "    212    312   .   912\r\n" );
document.write( "    ...    ...   .   ...\r\n" );
document.write( "    219    319   .   919\r\n" );
document.write( "\r\n" );
document.write( "having '1' in the tens position,\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "plus 8*9 = 72  other numbers from 201 to 991 of the table \r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "    201    301   .   901\r\n" );
document.write( "    221    321   .   921\r\n" );
document.write( "    231    331   .   931\r\n" );
document.write( "    ...    ...   .   ...\r\n" );
document.write( "    291    391   .   991\r\n" );
document.write( "\r\n" );
document.write( "having '1' in the units position and not having '1' in the tens position.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "In all, there are  100 + 80 + 72 = 252 such numbers.\r\n" );
document.write( "

\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

\n" );