That math tutorial tells you how to take, add or subtract a percentage, all of them being a multiplication.
If you wish to know more about percentages, look to our two blog posts:
https://mathedu.academy/Blog/?post=ad..., and https://mathedu.academy/Blog/?post=ma....
On this page of the site you can watch the video online Math Tutorial: The Percentages Manipulation with a duration of hours minute second in good quality, which was uploaded by the user The Practical Mathematics Channel of Mathedu 31 March 2020, share the link with friends and acquaintances, this video has already been watched 157 times on youtube and it was liked by 2 viewers. Enjoy your viewing!