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P (-zo < Z < zo) = 0.322?


New member
Feb 4, 2012
I need to find the value of -zo and zo - Unfortunately, my prof isn't the clearest, and my brain hasn't quite figured out the ins and outs of statistics yet - so I'm sure that this is simple, but I'm absolutely baffled!

P(-zo < Z <zo) = .3220, using the table of standard normal probabilities.

When I work through it in my head, I would subtract 3.220 from 1(total probability), and then divide that probability by two, find the zo for that, and then add/subtract it to 0? Does this make sense?

Thanks so much!
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