Joko's Ninja Exchange rewards!

Whats this misunderstanding that it should be price of 10 white scrolls... aside from that being a lot, these should be worth more then 10 WS + 10 10% scrolls, cuz chance of all 10 10% failing is still (90% ^ 10 power) 34.867844% chance. I mean most of the time you will get one of the 10 to work, but this will work 100% or the time.