We have that

set of data [8, 12, 15, 17, 18]

step 1
Find the mean
[8+ 12 + 15 + 17 + 18]/5-------> 70/5------> 14

step 2
for each number: subtract the Mean and square the result
(8-14)²----->36
(12-14)²----> 4
(15-14)²----> 1
(17-14)²----> 9
(18-14)²----> 16

step 3
 work out the mean of those squared differences
[36+4+1+9+16]/5-----> 66/5-----> 13.2----> this value is called the "Variance"

step 4
Take the square root of that
standard desviation=√13.2-----> 3.63-------> 4

the answer is
4

7 0

3 years ago

Need help solving this limit problem.

evablogger [386]

Answer:

c= -1.8

Step-by-step explanation:

A function is continuous at a point x if the limits at x from above and below coincide (are equal). Hence,

Limit from above: $\lim_{x\rightarrow\-1^+}f(x)=4c(-1)=6 = -4c-6$

Limit from below: $\lim_{x\rightarrow\-1^-}f(x)=c(-1)^2+3=c+3$

And so when these limits are equal we obtain

$c+3=-4c-6\\5c=-9\\c=-1.8$

3 0

4 years ago

The prices of three t-shirts styles are $24, $30 and $36. the probability of choosing a $24 t-shirt is 1/6. the probability of c

Slav-nsk [51]

$\text{Answer} : \text{The expected value of a t-shirt is \$31.}$

Explanation:

Since we have given that

The prices of three t-shirts styles i.e $24, $30, $36 with their probability is given by

$\frac{1}{6}, \frac{1}{2},\frac{1}{3}$

As we know that,

$E(X)= \sum_{1}^{3}x_iP(x_i)$

$\text{where} x_i \text{ is the prices of t- shirts styles}$

Now,

$x_1= \$24 , x_2=\$30 , x_3=$36$

and

$P(x_1)=\frac{1}{6},P(x_2)=\frac{1}{2}, P(x_3)=\frac{1}{3}$

So,

$E(X)= 24\times \frac{1}{6}+30\times\frac{1}{2}+36\times \frac{1}{3}\\=4+15+12\\=31$

So, the expected value of a t-shirt = $31.

4 0

3 years ago

9 and 5/12 - 3 and 2/3

lana [24]

Recall to always convert the mixed fractions to "improper" fractions first,

$\bf \stackrel{mixed}{9\frac{5}{12}}\implies \cfrac{9\cdot 12+5}{12}\implies \stackrel{improper}{\cfrac{113}{12}}
\\\\\\
\stackrel{mixed}{3\frac{2}{3}}\implies \cfrac{3\cdot 3+2}{3}\implies \stackrel{improper}{\cfrac{11}{3}}\\\\
-------------------------------\\\\
\cfrac{113}{12}-\cfrac{11}{3}\impliedby \textit{clearly our LCD is 12}\implies \cfrac{113-(4)11}{12}
\\\\\\
\cfrac{113-44}{12}\implies \cfrac{69}{12}\implies 5\frac{9}{12}$

5 0

3 years ago