How to work out the percentage of amount mentally.
The best bit - you can learn it instantly and apply it straight away! It's easy, fast and you'll be working out percentages of amounts in no time.
To donate to the tecmath channel:[ Ссылка ]
To support tecmath on Patreon: [ Ссылка ]
To buy tecmath mechandise: [ Ссылка ]
Ещё видео!