Elixir collectors and gold mines

I have an idea about elixir and gold collectors about boosting.
You can choose the boosting of mines and elixir because some players do not spend money on the game for gems.
There are time you need gold or elixir to upgrade but you don't have enough gems for boost so I think somethink.
1 day boost x1.5 = 4 gems
2 day boost x2 = 5 gems
3 day boost x3 = 7 gems
I wanna say for the price of boost is depends of the production you will choose..


My English isn't so good if I did any mistake or you can't understand some think please tell me. thank for the view <3 :)