Question

Convert ${111111}_2$ to base $10$.

Answer 1

${111111}_2=1\times 2^5+1\times 2^4+1\times 2^3+1\times 2^2+1\times 2^1+1\times 2^0$
$=32+16+8+4+2+1={63}_{10}$
Therefore ${111111}_2={63}_{10}$