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3 years ago

Tom has 3 kids, the product of their ages is 72. What is the sum of their ages?

Mathematics

2 answers:

choli [55]3 years ago

8 0

To find that, let's represent their ages by x
x+x+x=72
3x/3=72/3
x=24
Therefore all of them are 24 years old.

mafiozo [28]3 years ago

5 0

Their ages are 24 years old each.

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Please help me!! Please

Katen [24]

X is less than or equal to -3
explanation
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3 0

3 years ago

Please Help Me With This Math Problem

gizmo_the_mogwai [7]

Answer:

Yes the relationship is linear and given by:

$y+2=-\frac{5}{4} \,(x+9)$ (first option of your list)

Step-by-step explanation:

Yes, it is a linear expression. As we did in previous exercises, we calculate the difference between consecutive y values of the table, and write down the answers we get:

-7-(-2) = -7+2 = -5

-12-(-7) = -12 +7 = -5

-17 - (-12) = -17 + 12 = -5

We notice that all of them give "-5"

Now we evaluate the difference between consecutive x-values in a similar fashion:

-5 -(-9) = -5+9 = 4

-1-(-5) = -1+5 = 4

3-(-1) = 3+1 = 4

We see that they all give 4 as the difference.

That means that the rate of change $\frac{y_2-y_1}{x_2-x_1} =\frac{y_3-y_2}{x_3-x_2}=\frac{y_4-y_3}{x_4-x_3}=\frac{-5}{4}$

This means that the slope (rate of change) of the line is "-5/4"

We can now use the general point-slope form to write the equation of the line, using the first pair of the table as our selected point, and using "-5/4" for the slope:

$y-y_0=m\,(x-x_0)\\y-(-2)=-\frac{5}{4} \,(x-(-9))\\y+2=-\frac{5}{4} \,(x+9)$

which is the first expression listed among your possible answer choices.

4 0

3 years ago

In a recent study of 42 eighth graders, the mean number of hours per week that they watched television was 19.6. Assume the popu

olya-2409 [2.1K]

Answer:

$19.6-2.42\frac{5.8}{\sqrt{42}}=17.43$

$19.6+2.42\frac{5.8}{\sqrt{42}}=21.77$

And the best option for this case would be:

a. (17.5, 21.7)

Step-by-step explanation:

Information given

$\bar X= 19.6$ represent the sample mean

$\mu$ population mean

$\sigma= 5.8$ represent the population deviation

n=42 represent the sample size

Confidence interval

The confidence interval for the mean is given by the following formula:

$\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}$ (1)

The degrees of freedom, given by:

$df=n-1=42-1=41$

Since the Confidence is 0.98 or 98%, the significance would be $\alpha=0.02$ and $\alpha/2 =0.1$ , and the critical value would be $t_{\alpha/2}=2.42$