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Hey there! We divided the number by 100 to get the decimal form of the percentage. If you write the number in standard format, $5.0\times10^{-5}$% will be 0.00005. If you divide this number by 100, you will get 0.0000005, which is equivalent to $5.0\times10^{-7}$.

Recall that 100 can also be written as $10^2$ or $1.0\times10^2$ . So you can also express the calculation as: $\left(5.0\times10^{-5}\right)\div\left(1.0\times10^2\right)$ . When dividing scientific notations with the same base, you subtract the exponents and divide the coefficients:  5.0 ÷ 1.0 = 5.0 (coefficient) and (–5) – 2 = –7 (exponents). So, the final result is $5.0\times10^{-7}$.