Jenny bought a 5 notebooks and 2 pencils, and the total was 9 dollars.

1 answer:

6 0

You would solve this with simultaneous equations, so if we write it as:
5n + 2p = 9
3n + 2p = 6
(subtract)
2n = 3
÷ 2
notebooks = 1.5

Now you would substitute it in:
(3 × 1.5) + 2p = 6
4.5 + 2p = 6
- 4.5
2p = 1.5
÷ 2
pens = 0.75

So your final answer is notebooks are $1.50 and pens are $0.75, I hope this helps!

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Probability of exactly x sucesses on n repeated trials, with p probability.

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$E(X) = np$

The standard deviation of the binomial distribution is:

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In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

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