MathDB
Counting in Base 4

Source:

February 15, 2009
modular arithmeticnumber theory

Problem Statement

In our number system the base is ten. If the base were changed to four you would count as follows: 1,2,3,10,11,12,13,20,21,22,23,30,… 1,2,3,10,11,12,13,20,21,22,23,30,\ldots The twentieth number would be: <spanclass=′latex−bold′>(A)</span> 20<spanclass=′latex−bold′>(B)</span> 38<spanclass=′latex−bold′>(C)</span> 44<spanclass=′latex−bold′>(D)</span> 104<spanclass=′latex−bold′>(E)</span> 110 <span class='latex-bold'>(A)</span>\ 20 \qquad<span class='latex-bold'>(B)</span>\ 38 \qquad<span class='latex-bold'>(C)</span>\ 44 \qquad<span class='latex-bold'>(D)</span>\ 104 \qquad<span class='latex-bold'>(E)</span>\ 110
Back to ProblemsView on AoPS