working out % chance?

[machine]

I havent done GCSE maths for years but am good at maths but for some reason cant work this out. assuming there is a 1 in 22 chance of getting in the deal or no deal chair, how do i work out what the odds are of being picked after 1 show,2 shows,etc,etc also how do you combine odds of something happening acummualtively for example 50% 20% 9% 14% is it 0.5x0.2x0.09x0.14=0.126%? chance of happening

sorry for being newbish

cheers guys