The base of the decimal number system is ten, meaning, for example, that 123 \equal{} 1\cdot 10^2 \plus{} 2\cdot 10 \plus{} 3. In the binary system, which has base two, the first five positive integers are 1,10,11,100,101. The numeral 10011 in the binary system would then be written in the decimal system as:
<spanclass=′latex−bold′>(A)</span>19<spanclass=′latex−bold′>(B)</span>40<spanclass=′latex−bold′>(C)</span>10011<spanclass=′latex−bold′>(D)</span>11<spanclass=′latex−bold′>(E)</span>7