59. A number was increased by $25 \%$. By what percentage does the resulting value need to be decreased to return to the original number?

10
59. Answer. By $20 \%$.

Translate the above text into English, please retain the original text's line breaks and format, and output the translation result directly. 

Note: The note is for your understanding and should not be included in the output. Here is the correct format:

59. Answer. By $20 \%$.