Ask question

Ask question

All categories

3 years ago

10

The wind speed changed negative 5 mph every hour for w hour's. the total change was negative 30 mph. How many hours did the chan

ge take?

1 answer:

nasty-shy [4]3 years ago

8 0

6 hrs it took to change

You might be interested in

Write an equation for the line perpendicular to 4x - 12y = 2 and passing through point (10, -1)

MrMuchimi

Answer:

3x+y=-31

Step-by-step explanation:

$4x - 12y = 2\\12y = 4x-2\\y=\frac{x}{3}-\frac{1}{6}$

Slope of perpendicular line is -3.

$y=-3x+b$

Sub in the point (10, -1)

$-1=-3(10)+b\\-1=30+b\\b=-31\\y=-3x-31\\3x+y=-31$

8 0

3 years ago

PLEASE HELP THIS IS DUE!!!

Rashid [163]

Answer:

432

Step-by-step explanation:

b x h (base x height)

the base is 27 yards and the height is 16.

27 x 16 = 432

5 0

3 years ago

What is the circumference of the circle?

VashaNatasha [74]

What is the circumference of the circle?

answer: D) 69.08

explanation:

7 0

3 years ago

Read 2 more answers

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

A store is instructed by corporate headquarters to put a markup of 25% on all items. An item costing $16 is displayed by the s

tigry1 [53]

Answer:

$20

Step-by-step explanation:

the manager's error could likely be putting the percentage mark up rather than the markup price added to the original price

25%×16

= $4

mark up price= (16+4)$

= $20

7 0

3 years ago