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2 years ago

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Stacey earns $15 each week plus $.50 for each customer on her paper route.she wants to earn at least $25 each week. What equatio

n can she use to find x, the number of customers she needs to make exactly $25?

1 answer:

andrezito [222]2 years ago

3 0

Answer:

15 + .5x = 25

Step-by-step explanation:

.5x = 10

x = 20

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Write a function G whose graph represents a reflection in the y-axis of the graph of f (x) = |2x–1|+3

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Answer: Did you find an answer yet?? Lol

Step-by-step explanation:

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2 years ago

Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.2.a. If the distri

zalisa [80]

Answer:

a

$P(\= X \ge 51 ) =0.0062$

b

$P(\= X \ge 51 ) = 0$

Step-by-step explanation:

From the question we are told that

The mean value is $\mu = 50$

The standard deviation is $\sigma = 1.2$

Considering question a

The sample size is n = 9

Generally the standard error of the mean is mathematically represented as

$\sigma_x = \frac{\sigma }{\sqrt{n} }$

=> $\sigma_x = \frac{ 1.2 }{\sqrt{9} }$

=> $\sigma_x = 0.4$

Generally the probability that the sample mean hardness for a random sample of 9 pins is at least 51 is mathematically represented as

$P(\= X \ge 51 ) = P( \frac{\= X - \mu }{\sigma_{x}} \ge \frac{51 - 50 }{0.4 } )$

$\frac{\= X -\mu}{\sigma } = Z (The \ standardized \ value\ of \ \= X )$

$P(\= X \ge 51 ) = P( Z \ge 2.5 )$

=> $P(\= X \ge 51 ) =1- P( Z < 2.5 )$

From the z table the area under the normal curve to the left corresponding to 2.5 is

$P( Z < 2.5 ) = 0.99379$

=> $P(\= X \ge 51 ) =1-0.99379$

=> $P(\= X \ge 51 ) =0.0062$

Considering question b

The sample size is n = 40

Generally the standard error of the mean is mathematically represented as

$\sigma_x = \frac{\sigma }{\sqrt{n} }$

=> $\sigma_x = \frac{ 1.2 }{\sqrt{40} }$

=> $\sigma_x = 0.1897$

Generally the (approximate) probability that the sample mean hardness for a random sample of 40 pins is at least 51 is mathematically represented as

$P(\= X \ge 51 ) = P( \frac{\= X - \mu }{\sigma_x} \ge \frac{51 - 50 }{0.1897 } )$

=> $P(\= X \ge 51 ) = P(Z \ge 5.2715 )$

=> $P(\= X \ge 51 ) = 1- P(Z < 5.2715 )$

From the z table the area under the normal curve to the left corresponding to 5.2715 and

=> $P(Z < 5.2715 ) = 1$

So

$P(\= X \ge 51 ) = 1- 1$

=> $P(\= X \ge 51 ) = 0$

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2 years ago

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<span>Aiko incorrectly used the associative property by changing the order of the two complex numbers.</span>

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3 years ago

Read 2 more answers

the sum of kate's age and her mother's age is 52. Kates mother is 20 years older than kate. how old is each

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<span>The sum of Kate age and her mother's age is 52, so
K + M = 52
Kate's mother is 20 years older then Kate, so
M = 20 + K
How old is each person?
Since M = 20 + K, substitute it into the first equation, that is, replace M with 20 + K

So, K + (20 + K) = 52
K + 20 + K = 52
2K + 20 = 52
Subtract 20 from both sides:
2K = 52 - 20
2K = 32
divide both sides by 2 to get
K = 16
Now we can find M, since M = 20 + K = 20 + 16 = 36
Kate is 16 years old and her mother is 36 years old.
Hope this helps!!1</span>

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3 years ago

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Misha Larkins [42]

Answer:

$x^{2} -3x-28$

Step-by-step explanation:

To find this equation in standard form, first, write it in factored form. This looks like $y=(x+4)(x-7)$ . Then, multiply the polynomials using the FOIL (First, Outside, Inside, Last) method.

Following the FOIL method, you should multiply the first terms in each binomial, $x*x$ , which equals $x^{2}$ .
Then, the outside terms, $x*-7$ . This equals $-7x$ .
Next, the inside terms, $4*x$ $=4x$ .
Finally, the last terms, $4*-7$ , this equals $-28$ .

Then, add all of the terms together $x^{2} + -7x+4x+-28$ . To get the standard form, combine like terms, this comes out to $x^{2} -3x-28$ .

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3 years ago