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1 year ago

15

Barbara draws pens randomly from a box containing 5 pens of the same shape and size. There is 1 green pen, 3 red pens, and 1 blu

e pen. She draws 1 red pen and then another red pen without replacing the first one. Find the probability of drawing 1 red pen followed by another red pen, and show the equation used.

1 answer:

Vinil7 [7]1 year ago

8 0

The contidion lets to establish that the events are independent.

Probability is the number of positive results / number of total events

The probability of drawing the first red pen is 3/5.

The probability of drawing the second red pen is 2/4

The combined propability is (3/5)*(2/4) = 6/20 = 3/10 = 0.30

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Substitution simply means replacing the variable y in the second equation with its equivalent x+3 from the first equation.

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On a coordinate plane, a cube root function goes through (negative 2.5, negative 3.5), crosses the y-axis at (0, negative 3), ha

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Answer:

$g(x) = \sqrt[3]{x-1} - 2$

Step-by-step explanation:

We want to find h and k in:

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At the inflection point, the second derivative is equal to zero, so:

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All data, used or not, are shown in the picture attached.

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2 years ago

A hospital finds that 22% of its accounts are at least 1 month in arrears. A random sample of 425 accounts was taken. What is th

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8.85% probability that fewer than 82 accounts in the sample were at least 1 month in arrears

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However, we are working with a large sample. So i am going to aproximate this binomial distribution to the normal.

Binomial probability distribution

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

Can be approximated to a normal distribution, using the expected value and the standard deviation.

The expected value of the binomial distribution is:

$E(X) = np$

The standard deviation of the binomial distribution is:

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Normal probability distribution

Problems of normally distributed samples can be solved using the z-score formula.

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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What is the probability that fewer than 82 accounts in the sample were at least 1 month in arrears

This probability is the pvalue of Z when X = 82. So

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

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8.85% probability that fewer than 82 accounts in the sample were at least 1 month in arrears

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1 year ago

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Answer:

The age of Sue could be 7 years

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Jenny is 8 years older than twice her cousin Sue's age.

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The second equation will be :

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Now rearrange both equations :

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The age of Sue could be 7 years.

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1 year ago