MathDB
Removing Leftmost Digit

Source:

January 2, 2009

Problem Statement

How many four-digit numbers N N have the property that the three-digit number obtained by removing the leftmost digit is one ninth of N N? <spanclass=latexbold>(A)</span> 4<spanclass=latexbold>(B)</span> 5<spanclass=latexbold>(C)</span> 6<spanclass=latexbold>(D)</span> 7<spanclass=latexbold>(E)</span> 8 <span class='latex-bold'>(A)</span>\ 4 \qquad <span class='latex-bold'>(B)</span>\ 5 \qquad <span class='latex-bold'>(C)</span>\ 6 \qquad <span class='latex-bold'>(D)</span>\ 7 \qquad <span class='latex-bold'>(E)</span>\ 8