SOLUTION: A sequence of numbers begins with the numbers -10,20,30,..., and each term afterward is the product of the preceding three terms.How many of the first 101 terms of this sequence ar

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Question 1018248: A sequence of numbers begins with the numbers -10,20,30,..., and each term afterward is the product of the preceding three terms.How many of the first 101 terms of this sequence are positive?
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
We only care whether the terms are negative or positive, and not what they are.

The 4th term is negative since the product of 1 negative number and two positive numbers is negative. Doing this, we have:

N, P, P, N, N, P, P, N...

So it repeats NPPN. The first 100 terms will have 50 positive terms, and the 101th term is negative, so there are 50 positive terms total.