$ \frac{1/3 \times 10^{7}}{0/0000005} = \frac{1/3 \times 10^{7}}{5 \times 10^{-7}} = \frac{13 \times  10^{-1} \times10^{7}}{5 \times 10^{-7}} = \frac{13}{5} \times \frac{10^6}{10^{-7}} \\ =\frac{13 \times 2}{5 \times 2} \times 10^{13} = \frac{26}{10} \times 10^{13} = 2/6 \times 10^{13} $