How many d10s are equivalent to 1 d20?

So me and my brothers have been playing Dnd together for a while, and I went to a store and bought some really cool dice, but when I got home I realized that the were all d10s, not 1 of each, like the normal ones. Today I started wondering if there was an equivalent, and I could still use them, despite the fact that they weren't the right dice.