Step-by-step explanation:
Let the required number be n
[tex] \therefore \: \frac{90}{100} \times n = x \\ \\ \therefore \: \frac{9}{10} \\ \\ \therefore \:n = \frac{10}{9} x \\ \\ \therefore 100\% \: of\:n = \frac{10}{9} x \times 100\% \\ \\ = \frac{10}{9} x \times \frac{100}{100} \\ \\ = \frac{10}{9} x \\ [/tex]
NOTE: A number is always 100% in itself.
