How do you calculate the eviolite boost?

Question

I honestly have no idea. What's an equation that I would have to use to know how much my Pokemon's Def + SpDef will increase with the eviolite?

Answer 1

Eviolite boost Defenses of unevolved Pokémon (which can evolve) by 50%

Comments

So basically multiply the current defense and S.Defense by 1.5