Assumptions: -1- You had a 3 bit register with each bit in a mix of both states — states 0 and state 1 -2- You then perform operations on the register When you perform the operation you will be performing the operation on all the possible values 000 through 111. Thus is explained the parallelism of quantum computing. That is its advantage over classical computing. If you do not understand how a physical system can be in both states at the same time you need to go back and study more quantum mechanics. More detailed explaination here An introductory course online
AdEx uses the Ethereum block chain.