You can read 9 pages of a book in 4 minutes so you can read 18 pages is a book in 8 minutes and so on and so forth
The first five terms are found by plugging in 1, 2, 3, 4, and 5 for n.
<span>3(1) - 2 = 13(2) - 2 = 43(3) - 2 = 73(4) - 2 = 10<span>3(5) - 2 = 13 is this what u mean???
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The reason why the sum of your probabilities equals 0.5 is because you're only considering half of the problem--i.e. the probabilities for only one gender. For example, the probability that there are only three children and all are boys is 1/8. But, remember, it could be the case that there are three children and all are girls. Thus, the probability that there are three children is 1/4--not 1/8. Thus, multiply your result for P(X=4) and P(X=5) by 2 and you should end up with the right answer...