The shoe store has twice as many black shoes as it does brown shoes The total number of shoes is 66 How many brown shoes are there?

There are 22 brown shoes and 44 black shoes.

To do this, you divide it by three (two thirds of the shoes are black, one third is brown - that's where you get 3 from) and then give the black shoes 2 shares and the brown shoes 1.

Someone please explain this better than me!