I really need help please

A data set with a mean of 34 and a standard deviation of 2.5 is normally distributed

tresset_1 [31]

Answer:

a) $z= \frac{34-34}{2.5}= 0$

$z= \frac{39-34}{2.5}= 2$

And we want the probability from 0 to two deviations above the mean and we got 95/2 = 47.5 %

b) $P(X$

$z= \frac{31.5-34}{2.5}= -1$

So one deviation below the mean we have: (100-68)/2 = 16%

c) $z= \frac{29-34}{2.5}= -2$

$z= \frac{36.5-34}{2.5}= 1$

For this case below 2 deviation from the mean we have 2.5% and above 1 deviation from the mean we got 16% and then the percentage between -2 and 1 deviation above the mean we got: (100-16-2.5)% = 81.5%

Step-by-step explanation:

For this case we have a random variable with the following parameters:

$X \sim N(\mu = 34, \sigma=2.5)$

From the empirical rule we know that within one deviation from the mean we have 68% of the values, within two deviations we have 95% and within 3 deviations we have 99.7% of the data.

We want to find the following probability:

$P(34 < X$

We can find the number of deviation from the mean with the z score formula:

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

And replacing we got

$z= \frac{34-34}{2.5}= 0$

$z= \frac{39-34}{2.5}= 2$

And we want the probability from 0 to two deviations above the mean and we got 95/2 = 47.5 %

For the second case:

$P(X$

$z= \frac{31.5-34}{2.5}= -1$

So one deviation below the mean we have: (100-68)/2 = 16%

For the third case:

$P(29 < X$

And replacing we got:

$z= \frac{29-34}{2.5}= -2$

$z= \frac{36.5-34}{2.5}= 1$

For this case below 2 deviation from the mean we have 2.5% and above 1 deviation from the mean we got 16% and then the percentage between -2 and 1 deviation above the mean we got: (100-16-2.5)% = 81.5%

7 0

2 years ago

Joani has some stuffed animals. She has 2 times as many as Lily. Lily has 6 stuffed animals. Joanie gave 2 away and bought 4 mor

8090 [49]

We start with his golf balls. He has four, so three times that number is 12. He has 12 baseballs. If we subtract 5 from 12, we can find how many tennis balls he has. So, Wyatt has 7 tennis balls.

8 0

3 years ago

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Please help!!! How many coefficients does this polynomial have in its complete form, including any missing terms?

frez [133]

-5x^3 + 2x^2 + 1

a coefficient is the number that is multiplied by the variable.For instance, the coefficient of 2x is 2....because 2 (the number) is multiplied by the variable x.

so in ur problem....there are 2 coefficients..-5 and 2.

** the number 1 is not a coefficient, it is a constant...a " loner " with no variables (letters) attached.

** and if u have just the letter...such as n, the coefficient to that is 1 but the one is just not written...it is actually 1n.

okay...I am gonna shut up now :)

7 0

2 years ago

Vertex of an absolute value graph ______ of the graph.

Inga [223]

Answer:

is the axis of symmetry

Step-by-step explanation:

i believe this is the answer :)

5 0

2 years ago

Evaluate the expression x³ when x=0.2

Talja [164]

I believe the answer is 0.008

because

0.2 × 0.2 × 0.2 is equivalent to 0.008

5 0

3 years ago

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