Radon is a naturally occurring gas and is the second leading cause of lung cancer in the United States. It comes from the natural breakdown of uranium in the soil and enters buildings through cracks and other holes in the foundations. Found throughout the United States, levels vary considerably from state to state. Several methods can reduce the levels of radon in your home, and the Environmental Protection Agency ecommends using one of these if the measured level in your home is above 4 picocuries per liter. Four readings from Franklin County, Ohio, where the county average is 9.32 picocuries per liter, were 5.2, 13.8, 8.6, and 16.8.

Required:
a. Find the mean step-by-step.
b. Find the standard deviation step-by-step.

Answers

Answer 1

Answer:

a) mean =  11.1

b) Standard Deviation = 5.191

Step-by-step explanation:

Given the data in the question;

x = 5.2, 13.8, 8.6, and 16.8

sample n = 4

so;

            x            ( x - mean)²

          5.2             34.81

          13.8            7.29

          8.6             6.25

          16.8            32.49

∑        44.4            80.84

a) Mean

Mean = total sum of the sample divided by the sample size

mean = ∑x / n

we substitute

mean = 44.4 / 4

mean =  11.1

b)

Standard Deviation is the Square root of variance;

Variance = ∑(x-mean)² / n - 1

we substitute from the above table

Variance =  80.81 / 4 - 1

Variance =  80.81 / 3

Variance =  26.94667

now since Standard Deviation is the Square root of variance;

Standard Deviation = √Variance

Standard Deviation = √26.94667

Standard Deviation = 5.191


Related Questions


Lindsey plans on visiting her friend two states over. The distance to her friend is 1188 miles. If she leaves on Friday and drives 7 hours at a time at 60 mph, how many days will she travel? (Round your answer to whole days

Answers

Answer:

Do you mean 7 hours a day? If so:

7*60=420

1188/420=2.82ish which rounds to 3 days.

Step-by-step explanation:

An office supply store recently sold a black printer ink cartridge for ​$14.99 and a color printer ink cartridge for ​$23.99. At the start of a recent fall​ semester, a total of 64 of these cartridges was sold for a total of ​$1157.36. How many of each type were​ purchased?

Answers

Let B be the number of Black printer ink cartridges and C be the number of color printer ink cartridges.

49 were sold in total, hence,

B+C= 49 ------------(1)

Also, its given that

18.99 B + 27.99 C = 1146.51---------(2)
Multiplying (1) by 18.99,

18.99 B+ 18.99 C= 930.51 ------(3)

Now, subtracting (3) from (2),

18.99 B + 27.99 C = 1146.51
18.99 B+ 18.99 C= 930.51
------------------------------------
9 C = 216
C= 24

We know, B+ C= 49
Hence B = 49-24 = 25

Hence, number of Black printer ink cartridges = 25 and color printer ink cartridges = 24.

(3/4 - 1/5) ÷ (5/2 - 1/3) xfa ayuda con procedimiento rapido​

Answers

Answer:

33/130

Step-by-step explanation:

3/4 - 1/5 = 11/20

5/2 - 1/3 = 2 and 1/6

11/20 divided by 13/6 = 33/130

Which ratio represents the number of orders for pepperoni pizza to cheese pizza?4:5 5:4 StartFraction 10 Over 8 EndFraction StartFraction 18 Over 10 EndFraction

Answers

Answer:

well cheese is better ;)

Step-by-step explanation:

Determine the type of bias involved. In a study of the effectiveness of wearing seat belts, a group of people who had survived car accidents in which they had not worn seat belts reported that seat belts would not have helped them. The type of bias involved in the given information i

Answers

Answer:

Non-response bias also known as Participation Bias

Step-by-step explanation:

The type of bias being demonstrated in this scenario is known as Non-response bias also known as Participation Bias. This is happening in this scenario because the individuals being surveyed have gone through the trauma of a car accident and survived it. To them they are stating that seat belts would not have helped since they do not want to believe that they could have done something to prevent their injuries. This causes them to say nothing or provide false information which ultimately ruins the results of the study.

Ayşe'nin boyu Selin'in boyunun iki katından 0,3 m
fazladır.
Selin'in boyu 0,66 m olduğuna göre Ayşe'nin
boyu kaç m'dir?
A) 1.26
B) 1,48
C) 1,62
D) 1,71​

Answers

Answer:

english pls

Step-by-step explanation:

Answer:

metreyle ölçmek lazım WXQQDWRQCQ

What is the solution of the equation 5* - 1 = 45? Round your answer to the nearest ten-thousandth.

Answers

What does the * mean

Answer:

The answer is 3.3652

Step-by-step explanation:

Find the number in the thousandth place  

5

and look one place to the right for the rounding digit  

2

. Round up if this number is greater than or equal to  

5

and round down if it is less than  

5

.

3.365

Heres the picture, thank you!

Answers

Leg * /2 = hypotenuse
Hypotenuse divided by /2 = leg

12 divided by /2

Rationalize denominator:
12 * /2 divided by by /2 * /2

Simplify denominator:
12 * /2 divided by 2

Simplify:
6 * /2 or 4.24

Both x and y because it’s a 45-45-90 triangle

Answer:

x = 6√(2)x = 6√(2)y = 6√(2)

Step-by-step explanation:

Sides equal opposite to equal angles are always equal -----------<1>If one angle of triangle is 90°, then it is a right triangle, can find sides with the help of Pythagoras Theorem. -----------<2>The sum of all three sides of any triangle is 180°. -----------<3>

Given angles of triangle = 45° + 45° + 90° {from <3>}

x = y {because of <1>}

→ H² = P² + B² (Pythagoras Theorem) {from <2>}

→ (12)² = x² + y²

→ 144 = x² + x² [x = y]

→ 144 = 2x²

→ 144/2 = x²

→ 72 = x²

→ √(72) = x

→ 6√2 = x

→ x = y

so,

x = 6√2 = y

x = 6(2)y = 6(2)

HOPE THIS HELPS YOU

Follw me = 10 thanks

Mark as brainliest = 10 thanks

1 thanks to me = 2 thanks





If 2.5 kg of tomatoes cost $8.25, how much will you pay for 7 kg?

Answers

Answer:

$2.10

Step-by-step explanation:

first we want to find for one kg. one kg is $0.30.

Multiply that by 7 and you get $2.10

Answer:

$23.10

Step-by-step explanation:

8.25 ÷ 2.5 = 3.3

7 x 3.3 = 23.10

you have to find out how much money you pay per kg

you pay $3.30 per kg

therefore you have to multiply the kg (7) by the price (3.30) and that's why you get $23.10

hope this helps :)

1/3(4 + 18)-2²
PLIS I need help :(​

Answers

Answer:

10/3

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to Right

Step-by-step explanation:

Step 1: Define

1/3(4 + 18) - 2²

Step 2: Evaluate

(Parenthesis) Add:                                                                                          1/3(22) - 2²Exponents:                                                                                                      1/3(22) - 4Multiply:                                                                                                           22/3 - 4Subtract:                                                                                                          10/3

Hazel bought some donuts for $2.15 each. She also bought a drink for $3.12. She spent a total of $11.72. Write an equation to find how many donuts Hazel bought ​

Answers

Answer:

she had 4 donuts!

Step-by-step explanation:

her total was $11.72 minus the drink so $8.60 and divided by the cost of donuts $2.15 you get 4.

Answer:

(11.72 - 3.12) ÷ 2.15 = 4

Step-by-step explanation:

You can double check by doing (2.15 x 4) + 3.12 = 11.72

Find the indicated real \large nth root(s) of \large a.


\large n=6, \large a=64

Answers

Answer:

e

Step-by-step explanation:

PLEASE HELP M IN THE MIDDLE OF A TEST
A rock is thrown upward with a velocity of 12 meters per second from the top of a 25 meter high cliff, and it misses the cliff on the way back down. When will the rock be 3 meters from ground level? Round your answer to two decimal places.

Answers

Answer:

find t when

25 + 12t - 5t^2 = 3

using g=10 (easier than using 9.81)

Jolyn was paid $340 last week working 17 hours. What was Jolyn’s hourly pay? Do not include the units in your answer

Answers

Answer:

20

Step-by-step explanation:

It is mentioned that Jolyn made $340 in 17 hours last week. In order to evaluate this, you'll have to divide the money earned by the hours worked.

[tex]\frac{340}{17} =20[/tex]

Therefore, Jolyn makes $20 an hour as 20 x 17 = 340 which is correct,

URGENT HELP 30 POINTS

Answers

Answer:The answer is  pride 5

Step-by-step explanation:

If /Il m, what is the value of x?

Answers

Answer:

x= 137 hope it helps have a nice day

Answer:

137

Step-by-step explanation:

180-43 (these two angles plug into all the angles)

please help ill mark brainliest

Answers

Answer:

x=11.31

Step-by-step explanation:

Pythagorean theorem

12^2-4^2=x^2

144-16=x^2

x=11.31

HELP!
What is the determinant of [-4 3, -7 6]?

a. -24
b.-3
c. 3
d.45

Answers

Answer:

-3

Step-by-step explanation:

Answer:

It's B

Step-by-step explanation:

Who can help me with this ?

Answers

Answer:

Growth

Step-by-step explanation:

Since the the consistent exponent 5/2 is greater than 1 it will grow

https://homework.russianschool.com/resource?key=54457jiywiyhw

Answers

I m not sure I understand

Answer:

120

Step-by-step explanation:


I need help ASAP!!!!

Answers

Answer:

r=5

Step-by-step explanation:

25^3 = 15626

-5^3 = -125

5^3 = 125

15^3 = 3375

Answer:

R=5

Step-by-step explanation:

You first have to find the cube root

The cube root of 125 is 5

r=5

Ursula bougth dozen rollz of the first aid tape for the health office the rollz were divided equally into 4 boxes how many rolls are in each box

Answers

The answer is 3 rolls
Hope this helps :)

The graph of a function f is shown below.
Find one value of x for which f(x) = -4 and find f (2).
helppp pleaseeee

Answers

(0,-4) and (2,-3) are points on the graph. f(0) = -4
f(2) = -2

K 4x J 6x – 8 L 152° What is the measure of angle KJL? O A. 640 O B. 78° 0 C. 840 O D. 88°​

Answers

Answer:

D

Step-by-step explanation:

180-152= 28°

4x+6x-8+28=180

10x=160

x=16°

kjl= 6x-8= 88°

How do you plot 74.7284 on a base-10 number line?

Answers

Step-by-step explanation:

About between of 70 and 80.

A department of transportation's study on driving speed and miles per gallon for midsize automobiles resulted in the following data. Speed (Miles per Hour) 30 50 40 55 30 25 60 25 50 55 Miles per Gallon 29 26 26 22 29 31 21 35 25 26 Compute the sample correlation coefficient. (Round your answer to two decimal places.) Interpret the sample correlation coefficient. There is a strong negative relationship between the driving speed and miles per gallon. For driving speed between 25 and 60 miles per hour, higher speeds are associated with lower miles per gallon.

Answers

Answer:

R = -0.90 (2 decimal places)

Step-by-step explanation:

Given the data :

Speed (Miles per Hour) :

30

50

40

55

30

25

60

25

50

55

Miles per Gallon :

29

26

26

22

29

31

21

35

25

26

The correlation Coefficient, R shows the degree or level of relationship between the dependent and independent variable. A positive R value denotes a positive correlation while a negative R value denotes a negative relationship. R values should range between - 1 to +1 with values close to 1 and - 1 depicting strength while value of zero means no relationship exist.

Hence, R value of -0.90 depicts a strong negative relationship. Hence, higher speed are related to lower miles per gallon and vice versa.

Worth 20 points

Please answer these all in a fraction form! :) <3 ily all have a AMAZING day.

1. 1/8 ÷ 3/4 = ?
2. 3/5 ÷ 3/2 = ?
3. 4/1 ÷ 2/3 = ?
4.9/4 ÷ 6/5 = ?
5.22/4 ÷ 2/5 = ?​

Answers

Answer:

1. 1/8 ÷ 3/4 = 1/6

2. 3/5 ÷ 3/2 = 2/5

3. 4/1 ÷ 2/3 = 6

4.9/4 ÷ 6/5 = 15/8

5.22/4 ÷ 2/5 = 261/80

Step-by-step explanation:

Hope this Helped

how do I find "Z"? of possible can you do a step by step?​

Answers

Answer:

z = 7.5

Step-by-step explanation:

Polygon ABCD and polygon EFGH are similar, therefore, their sides would be proportional to each other. This means the ratio of their corresponding sides would be equal to each other.

BC corresponds to FG

CD corresponds to GH

Therefore:

8/6 = 10/z

4/3 = 10/z

Cross multiply

4*z = 10*3

4z = 30

4z/4 = 30/4

z = 7.5

uh yo how do i make histogram

Answers

Answer:

u can use desmos to help u.

Step-by-step explanation:

Missy read 1/12 of a book by Monday 1/4 of the book by Tuesday and 5/12 of the book by Wed. if the pattern continues how much of the book will she have read by Fri. draw a chart or explain​

Answers

Answer:

part A:

1/12 on day 1

1/4 or 3/12 on day 2

5/12 on day 3

Missy read 2/12 or 1/6 every day

Part B:

if day 1 is 1/12 and Friday is day 5 and she reads 2/12 per day

2/12 * 4 = 8/12

so 1/12 + 8/12 = 9/12 or 3/4 by Friday

Answer:

Monday: 1/12

Tuesday: 3/12

Wednesday: 5/12

Step-by-step explanation:

Other Questions
An experiment consists of tossing a die and then flipping a coin once if the number on the die is even. If the number on the die is odd, the coin is flipped twice. Use the notation "4H", for example, to denote the outcome that the die comes up "4" and the coin comes up "heads", and "3HT to denote the outcome that the die comes up 3 followed by a head and then a tail on the coin.a. Construct a tree diagram to show the 18 elements of the Sample Space S.b. List the elements corresponding to the event A that a number less than 3 occurs on the die.c. List the elements corresponding to the event B that two tails occur.d. List the elements corresponding to the event C that a head and tail occur.e. List the elements corresponding to the event A'.f. List the elements corresponding to the event A' B.g. List the elements corresponding to the event A B.h. Draw a Venn diagram to illustrate events A, B, and C.i. Are A and B mutually exclusive? Are A and C mutually exclusive? Are B and C mutually exclusive? State if the two triangles are congruent. If they are, state how you know. Round 43.827 to the nearest hundredth. anyone good with 9th grade history?? :) If a buoyancy box is not airtight and fills with water, would it have negative, neutral, or positive buoyancy? Defend your answer. ( I know it isn't the right subject but it didn't have the science option) Please help!!! will give brainliest! PLEASE ANSWER FAST!!!What is the benefit of asking a clarifying question?It allows the presenter to go more in-depth on a subject.It helps the audience to understand a confusing section of apresentation.It allows the presenter to connect two concepts together.It allows someone to look smarter than theirpeers. Math Help plz. I cant figure it out. What is a direct democracy ? How is adding and subtracting rational numbers similar and different than adding and subtracting integers? Can someone help me write an introduction about qualities of a good student? 2. Which technique is this an example of: 'Sophie woke up slowly, she smiled as the sun shonebrightly through her window.a. Pathetic Fallacyb. Similec. Metaphord. Hyperbole Help this is really hard Give me a information or body of movie review about movie fast and furious. religion only makes suffering worseEvaluate this statement considering arguments for and against. In your answer you should: Refer to Christian teachings Refer to non-religious points of view Reach a justified conclusion (12) What do Wesley Harris and c mattrson decided to do? what message can you draw from the information/ picture below? Drag and drop each example under the appropriate heading. PLZ HELP ONLY HAVE 10 MINUTES La magnitud de un ngulo depende de la longitud de sus lados verdad o falso Which expression is the sum of-5.3m + 3.4n and 2.5n + 2.8m?A. -2.8m + 6.2nB. -2.5m + 5.9nC.-8.1m + 0.9nD. 2.5m + 5.9n+B