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**WeeG** Hello, I could use some help with this one...cheers !!

A big company produce boxes with a brand new machine that produce 10 boxes (with identical size) every minute, 7 black and the rest white (in random order). The machine pack the boxes in pairs in a special package right when it leave the production line. Let X be a random variable of the number of packages with 2 black boxes, in a minute.

1. Build the probability function of X.

2. Calculate the probability that out of 3 hours or producing, there will be at least

70 minutes in which there will be found exactly 3 packages with 2 black boxes.

thank you !