R 3. The mean of 4 numbers is 8. Three of the numbers add up to 22. What is the last number?

Mathematics

1 answer:

statuscvo [17]2 years ago

7 0

<h2><em><u>Solution</u></em> : </h2>

let the last number be x

we know,

$\boxed{mean = \frac{sum \: \: of \: \: all \: \: observations}{number \: \: of \: \: observations} }$

So,

$\hookrightarrow \: 8 = \dfrac{22 + x}{4}$

$\hookrightarrow \: 8 \times 4 = 22 + x$

$\hookrightarrow \: 32 = 22 + x$

$\hookrightarrow \: x = 32 - 22$

$\hookrightarrow \: x = 10$

therefore, the last number is 10.

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Taya2010 [7]

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Beautiful question.

4 0

3 years ago

Will give brainliest!!

yawa3891 [41]

Answer:

$r=\frac{9\cos \theta}{\sin^2 \theta}$