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3 years ago

Is anyone good with this? I need help finding the answer.

Mathematics

1 answer:

dybincka [34]3 years ago

3 0

To solve this problem, we have to find the perimeter of the shape.
we already know that two of the sides are 82m, all we need to do is find the circumference of the semicircles.
to find circumference, you multiply the diameter of a circle by pi. since we have two identical semicircles, we have one full circle. 66•3.14=207.24
207.24+82+82=371.24
the answer is 371.24m

You might be interested in

What is the total surface area of the cone?

Ymorist [56]

T.S.A. = pi (7) (24) + pi (7)^2 = 168pi + 49pi = 217 pi cm^2 = more or less 681,73 cm^2

7 0

3 years ago

J.J.Bean sells a wide variety of outdoor equipment and clothing. The company sells both through mail order and via the internet.

melamori03 [73]

Answer:

99% confidence interval for the true mean difference between the mean amount of mail-order purchases and the mean amount of internet purchases is [$(-31.82) , $12.02].

Step-by-step explanation:

We are given that a random sample of 16 sales receipts for mail-order sales results in a mean sale amount of $74.50 with a standard deviation of $17.25.

A random sample of 9 sales receipts for internet sales results in a mean sale amount of $84.40 with a standard deviation of $21.25.

The pivotal quantity that will be used for constructing 99% confidence interval for true mean difference is given by;

P.Q. = $\frac{(\bar X_1-\bar X_2)-(\mu_1-\mu_2)}{s_p \times \sqrt{\frac{1}{n_1}+\frac{1}{n_2} } }$ ~ $t__n_1_+_n_2_-_2$

where, $\bar X_1$ = sample mean for mail-order sales = $74.50

$\bar X_2$ = sample mean for internet sales = $84.40

$s_1$ = sample standard deviation for mail-order purchases = $17.25

$s_2$ = sample standard deviation for internet purchases = $21.25

$n_1$ = sample of sales receipts for mail-order purchases = 16

$n_2$ = sample of sales receipts for internet purchases = 9

Also, $s_p =\sqrt{\frac{(n_1-1)\times s_1^{2}+(n_2-1)\times s_2^{2} }{n_1+n_2-2} }$ = $\sqrt{\frac{(16-1)\times 17.25^{2}+(9-1)\times 21.25^{2} }{16+9-2} }$ = 18.74

The true mean difference between the mean amount of mail-order purchases and the mean amount of internet purchases is represented by ( $\mu_1-\mu_2$ ).

Now, 99% confidence interval for ( $\mu_1-\mu_2$ ) is given by;

= $(\bar X_1-\bar X_2) \pm t_(_\frac{\alpha}{2}_) \times s_p \times \sqrt{\frac{1}{n_1} +\frac{1}{n_2}}$

Here, the critical value of t at 0.5% level of significance and 23 degrees of freedom is given as 2.807.

= $(74.50-84.40) \pm (2.807 \times 18.74 \times \sqrt{\frac{1}{16} +\frac{1}{9}})$

= [$-31.82 , $12.02]

Hence, 99% confidence interval for the true mean difference between the mean amount of mail-order purchases and the mean amount of internet purchases is [$(-31.82) , $12.02].

5 0

2 years ago

What number should be added to both sides of the equation to complete the square? x^2 – 6x = 5

NeTakaya

You will add $( \frac{-6}{2} )^{2}$
$(-3)^{2}$
9

5 0

3 years ago

Find COS

ehidna [41]

$\frac{9}{41}$

Step-by-step explanation:

The ratio cosine tell us that

In a right angled triangle, the cosine of an angle is the side adjacent to the angle divided by the hypotenuse of the triangle.

In other words,

$\cos(x) = \frac{adj}{hyp}$

The side adjacent to angle a is 9. The hypotenuse is 41.

$\cos(a) = \frac{9}{41}$

6 0

2 years ago

Your 3 nieces and 3 nephews (6 children total) are visiting for the holidays. You must give them each a present. They all love l

marusya05 [52]

Answer:

The 6 Lego kits can be selected from the 9 available Lego kits in 84 ways.

Step-by-step explanation:

Use combinations to solve this problem.

Combination is defined as the selection of <em>r</em> elements from <em>n</em> distinct objects irrespective of the order. The objects cannot be replaced.

There are 9 Lego kits available.

And the total number of children is 6.

That is, we need to select 6 Lego kits from the 9 available Lego kits.

6 Lego kits can be selected from the 9 available Lego kits in $9\choose 6$ ways.

Solving the combination as follows:

${9\choose 6}=\frac{9!}{6!\times(9-6)!} \\=\frac{362880}{720\times6}\\ =84$

Thus, there are 84 ways to select 6 Lego kits from 9 available Lego kits.

4 0

2 years ago