Solve 5.7y - 3.9y I is not smart lolz

In which quadrant is point (12,-12) located

Delvig [45]

It is located in quadrant 3. Hope this helped :D

5 0

3 years ago

A quality analyst of a tennis racquet manufacturing plant investigates if the length of a junior's tennis racquet conforms to th

Burka [1]

Answer:

Confidence interval : $21.506$ to $24.493$

Step-by-step explanation:

A quality analyst selects twenty racquets and obtains the following lengths:

21, 25, 23, 22, 24, 21, 25, 21, 23, 26, 21, 24, 22, 24, 23, 21, 21, 26, 23, 24

So, sample size = n =20

Now we are supposed to find Construct a 99.9% confidence interval for the mean length of all the junior's tennis racquets manufactured at this plant.

Since n < 30

So we will use t-distribution

Confidence level = 99.9%

Significance level = α = 0.001

Now calculate the sample mean

X=21, 25, 23, 22, 24, 21, 25, 21, 23, 26, 21, 24, 22, 24, 23, 21, 21, 26, 23, 24

Sample mean = $\bar{x}=\frac{\sum x}{n}$

Sample mean = $\bar{x}=\frac{21+25+23+22+24+21+25+21+23+ 26+ 21+24+22+ 24+23+21+ 21+ 26+23+ 24}{20}$

Sample mean = $\bar{x}=23$

Sample standard deviation = $\sqrt{\frac{\sum(x-\bar{x})^2}{n-1}}$

Sample standard deviation = $\sqrt{\frac{(21-23)^2+(25-23)^2+(23-23)^2+(22-23)^2+(24-23)^2+(21-23)^2+(25-23)^2+(21-23)^2+(23-23)^2+(26-23)^2+(21-23)^2+(24-23)^2+(22-23)^2+(24-23)^2+(23-23)^2+(21-23)^2+(21-23)^2+(26-23)^2+(23-23)^2+(24-23)^2}{20-1}}$

Sample standard deviation= s = $1.72$

Degree of freedom = n-1 = 20-1 -19

Critical value of t using the t-distribution table $t_{\frac{\alpha}{2}$ = 3.883

Formula of confidence interval : $\bar{x} \pm t_{\frac{\alpha}{2}} \times \frac{s}{\sqrt{n}}$

Substitute the values in the formula

Confidence interval : $23 \pm 1.73 \times \frac{1.72}{\sqrt{20}}$

Confidence interval : $23 -3.883 \times \frac{1.72}{\sqrt{20}}$ to $23 + 3.883 \times \frac{1.72}{\sqrt{20}}$

Confidence interval : $21.506$ to $24.493$

Hence Confidence interval : $21.506$ to $24.493$

3 0

3 years ago

Read 2 more answers

In a sociology class there are 1414 sociology majors and 1111 non-sociology majors. 33 students are randomly selected to present

saul85 [17]

Answer: $0.4065$

Step-by-step explanation:

Given : In a sociology class there are 14 sociology majors and 11 non-sociology majors.

Total students = 14+11=25

Number of students are randomly selected = 3

Then, the number of ways to select 3 students from 25 students :-

$^{25}C_3=\dfrac{25!}{(25-3)!3!}=\dfrac{25\times24\times23\times22!}{22!3!}\\\\=2300$

Number of ways to select at least 2 of the 3 students re non-sociology majors :-

$^{14}C_1\times^{11}C_2+^{14}C_0\times ^{11}C_{3}\\\\=(14)\times\dfrac{11!}{2!(11-2)!}+(1)\times\dfrac{11!}{3!(11-3)!}\\\\=(14)(11\times5)+\dfrac{11\times10\times9}{6}\\\\=770+165=935$

The probability that at least 2 of the 3 students selected are non-sociology majors will be :-

$\dfrac{935}{2300}=0.40652173913\approx0.4065$

8 0

3 years ago

Toni paints a wall that is 9 feet tall and 13 feet wide.What is the area of the wall?

aksik [14]

Answer:

117 feet squared

Step-by-step explanation:

Multiply the height (9 feet) by the width (13 feet).

9 x 13 = 117

117 feet squared

Note: squared is added when describing area (it's used as an exponent in numbers)

6 0

2 years ago

I need to put in order from less then to greater then

rosijanka [135]

1.05
1.1
1.25
1.5
it all correct ^^

3 0

3 years ago