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3 years ago

What is the answer20+8r=-4r+5r

Mathematics

1 answer:

Naily [24]3 years ago

5 0

Answer:

The answer is r = -20/7

Step-by-step explanation:

20 + 8r = -4r + 5 r⇒ collect like term

20 + 8r = r⇒separate different terms in different sides

20 = r - 8r

20 = -7r⇒divide both sides by -7

r = 20/-7

r = -20/7

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A poll of 793 adults aged 18 or older asked about purchases that they intended to make for the upcoming holiday season. One of t

Ira Lisetskai [31]

Answer:

(0.5793, 0.6363)

Step-by-step explanation:

Given that a poll of 793 adults aged 18 or older asked about purchases that they intended to make for the upcoming holiday season. One of the questions asked about what kind of gift they intended to buy for the person on whom they would spend the most. Clothing was the first choice of 482 people.

i.e. sample proportion p= $\frac{482}{793} =0.608$

$q=1-p = 0.392$

Std error of p = $\sqrt{pq/n} =0.0173$

For 90% Z crtiical = 1.645

Hence margin of error = 1.645 * std error = 0.0285

Confidence interval 90%

= proportion ±margin of error

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3 years ago

10. Based on the diagram below, which statement is true?

Fofino [41]

Answer:

Part D is correct

Step-by-step explanation:

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3 years ago

1)Sheyna drive to the lake and back. It took two hours less time to get there than it did to get back. The average speed on the

ipn [44]

Answer:

8 hours

Step-by-step explanation:

Given:

Sheyna drives to the lake with average speed of 60 mph and

$v_1 = 60\ mph$

Sheyna drives back from the lake with average speed of 36 mph

$v_2 = 36\ mph$

It took 2 hours less time to get there than it did to get back.

Let $t_1$ be the time taken to drive to lake.

Let $t_2$ be the time taken to drive back from lake.

$t_2-t_1 = 2$ hrs ..... (1)

To find:

Total time taken = ?

$t_1+t_2 = ?$

Solution:

Let D be the distance to lake.

Formula for time is given as:

$Time =\dfrac{Distance}{Speed }$

$t_1 = \dfrac{D}{60}\ hrs$

$t_2 = \dfrac{D}{36}\ hrs$

Putting in equation (1):

$\dfrac{D}{36}-\dfrac{D}{60} = 2\\\Rightarrow \dfrac{5D-3D}{180} = 2\\\Rightarrow \dfrac{2D}{180} = 2\\\Rightarrow D = 180\ miles$

So,

$t_1 = \dfrac{180}{60}\ hrs = 3 \ hrs$

$t_2 = \dfrac{180}{36}\ hrs = 5\ hrs$

So, the answer is:

$t_1+t_2 = \bold{8\ hrs}$

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3 years ago

3(x+9)-4x=11x-13x+23

adoni [48]

Answer:

$\huge\boxed{x=-4}$

Step-by-step explanation:

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3 years ago

At what position on the number line is the red dot located?

raketka [301]

Answer:

C. 0.5..................

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2 years ago