Lin Ying belongs to an athletic club. In 800 m races her times are normally distributed with mean 128 seconds and standard deviation
4 seconds.
(a) What is the probability of her time in an 800 being between 120 and 130 seconds?
(b) What time will she beat in 70% of her races?
Julie belongs to the same club. In 800 m races 85% of her times are less than 140 seconds and 70% are less than 135 seconds. Her times are normally distributed.
(c) Find the mean and standard deviation of Julie's times, each correct to two significant figures.
(d) What is the probability that in an 800 m race Lin Ying will beat Julie?
(e) The club has to choose one of these two athletes to enter a major competition. In order to qualify for the final rounds it is necessary to achieve a time of 114 seconds or less in the heats. Which athlete should be chosen and why?

Answers

Answer 1

Answer:

Nine of the times for the first race were at least 16 seconds

Step-by-step explanation:

Here we have from the scatter plot, the times are given as

Time               Frequency

19                          2

18                          2

17                          2

16                          3

15                          1

Therefore, total number of times that are above 16 seconds in the first race is

3 + 2 + 2 + 2 = 9

Therefore, the first option is correct

Answer 2

Answer:

Step-by-step explanation:

The answer is below. Plesetake a look and it will help you


Related Questions

-15.8= y-24.3 please solve and get back quickly

Answers

Answer:

Y=17/2=8.500

I just took a test with this question

Devaughn's age is two times Sydney's age. The sum of their ages is 18. What is Sydney's age?

Answers

Answer:

Sydney's Age is 6

Step-by-step explanation:

6 x 2 = 12

12 + 6 = 18

Answer:

Sydney is 6

Step-by-step explanation:

You get this by dividing 18 by three, as one set of 6 is Sydney while tcice that is her brother.

LOOK AT PICTURE, THEN ANWSER QUESTION, WHOEVER IS CORRECT I WILL MARK BRAINIEST:)

Answers

Answer:

c is the correct answer

At the start of a month a customer spends $3 for a reusable coffee cup. She pays $2 each time she has the cup filled with coffee. At the end of the month she has paid
$53. Write an equation to show x number of refills she got for the month.

Answers

Equation: 3+2(x)=53
Answer: x=25

Evaluate:

12x+10 for x=−12

Answers

Answer:

-144?

Step-by-step explanation:

im not sure if that'll be the answer

Answer:

-134

Step-by-step explanation:

UMM SOMEONE CAN HELP ME I need to do this using the distributive property and collecting like terms.

8 − 4 ( 1/8r −3 1/2

Answers

The answer is 21 1/2. Hope this helps, love!

The Data set shows the ages of the members of two clubs.
CLUB A: 42, 38, 40, 34, 37, 46, 38, 45
CLUB B: 30, 44, 42, 61, 24, 27, 59, 65 m
(10 Points)
Find the mean age for CLUB A :

Answers

Answer:

it goes by  +4 and -4

Step-by-step explanation:

Answer: 40

You can find the mean for club A by adding up every number in the set and then dividing by the amount of numbers in the data set:

So first we add up 42+38+40+34+37+46+38+45
Which = 320

Now we divide that number by 8 because there are 8 numbers in the data set (all the numbers we added up):

320/8=40

So now we know that the mean age is 40!

Hope this helps :)!

The length of a rectangle is twice its width. Find its area, if its perimeter is 7 1/3 cm.

Answers

Answer:

241/81 cm^2

Step-by-step explanation:

[tex]2\: lenghts = wide\\\\lenght=x\\\\2x=wide\\\\Perimeter = 2(wide+lenght)\\\\P=2(2x+x)\\\\P=2(3x)\\\\P=7\frac{1}{3}\\\\\frac{22}{3}=6x\\\\x=\frac{22}{3*6}\\\\x=\frac{11}{9}\\\\width = 2x=2(\frac{11}{9})=\frac{22}{9}[/tex]

[tex]Area = lenght\times width\\\\Area = \frac{11}{9}\times\frac{22}{9}\\\\A=\frac{11*22}{9*9}\\\\A=\frac{242}{81}cm^2[/tex]

Answer:

[tex]2\frac{80}{81}[/tex] cm²

Step-by-step explanation:

A = lw

P = 2(l + w)

~~~~~~~~~~~

l = 2w

2(2w + w) = [tex]7\frac{1}{3}[/tex]

2(3w) = [tex]\frac{22}{3}[/tex]

3w = [tex]\frac{11}{3}[/tex]

w = [tex]\frac{11}{9}[/tex]

l = [tex]\frac{22}{9}[/tex]

A = [tex]\frac{22}{9}[/tex] × [tex]\frac{11}{9}[/tex] = [tex]\frac{242}{81}[/tex] = [tex]2\frac{80}{81}[/tex] cm²

Write the following phrase as an algebraic expression. Use n for a number." three increased by the quotient of a number and two a. 3 + 2 b. 3 + C! 312+ 2) d. 3 + 212 ​

Answers

Answer:

Write the following phrase as an algebraic expression. Use n for a number." three increased by the quotient of a number and two a. 3 + 2 b. 3 + C! 312+ 2) d. 3 + 212

Step-by-step explanation:

Write the following phrase as an algebraic expression. Use n for a number." three increased by the quotient of a number and two a. 3 + 2 b. 3 + C! 312+ 2) d. 3 + 212

Answer:

 

The answer is b. 3 +  n / 2

Step-by-step explanation:

if a rectangle have length of 10 inches and width of 8 inches what is the new area if each corner is cut by x^2

Answers

Answer:

[tex]80 - 4x^2[/tex]

Step-by-step explanation:

Area of a rectangle

A rectangle of width W and length L has an area of:

A = W.L

The given rectangle has a length of L=10 inches and a width of W=8 inches, thus its area is:

A = 8*10 = 80

[tex]A = 80\ in^2[/tex]

If each corner is cut by a square of x*x, then the total area will be:

[tex]A' = 80 - 4x^2[/tex]

The new area is [tex]\mathbf{80 - 4x^2}[/tex] square inches

1 Austin earned 47 out of 50 points on his math test. Marty earned a 92% on his math test. Who earned a higher score? Marty or Austin​

Answers

Answer:

Austin earned a higher score

Step-by-step explanation:

47/50 (Austin's score) = 94/100 (denominator is now 100) = 94% (converted to percentage) > 92% (Marty's score)

Hope this helps!

Answer:

Austin earned a higher score.

Step-by-step explanation:

Marty 50 * 0.92 = 46 points

find the difference between (-2,3) and (6,3) ​

Answers

Answer:

5.099

Step-by-step explanation:

Answer:

The difference between (-2,3) and (6,3) is 8

Step-by-step explanation:

A dinner table is 5 feet wide and 7 feet long.



Find the area of the table.





A.
75

B.
35

C.
30

D.
144

Answers

the answer is b, 35. have a nice day!
It’s b 35 I helped I think :)

5.2.21-T
Question Help
Assume that when adults with smartphones are randomly selected 44%use them in meetings or classes. If 17 adult smartphone users are randomly selected, find the probability that exactly 2 of them use their smartphones in
Meetings or classes

Answers

Answer:

0.004398

Step-by-step explanation:

Given that:

p = 44% = 0.44

Number of trials (n) = 17

Probability that exactly 2 of them use smartphones in meetings or classes =?

Using the binomial probability formula :

P(x = 2)

P(x = x) = nCx * p^x * (1 - p)^(n-x)

P(x = 2) = 17C2 * 0.44^2 * 0.56^15

P(x = 2) = 136 *0.1936 * 0.0001670399

P(x = 2) = 0.00439809

P(x = 2) = 0.004398

6) Calculate the slope of a line containing the points (-3,5) and (-7,11).

Answers

Slope: (y2-y1)/(x2-x1)
(11-5)/(-7+3) = 6/-4 = 3/-2
The slope is -3/2

slopev=

[tex]diffrence \: in \: y \: coordinate \\ diffrence \: in \: x \: coordinate[/tex]

so

Y=11_5 =6

X = -7_(-3) = -4.

slope = (-4,6)

make as brainlist

Assume that the readings are a random sample from a population that follows the normal curve. We perform a t-test to see whether the scale is properly calibrated. Find the corresponding P-value for this test..

Answers

Complete Question

Each of the following hypothetical data set represents some repeated weighing of a standard weight that is known to have a mass of 100 g. Assume that the readings are a random sample from a population that follows the normal curve. We perform a t-test to see whether the scale is properly calibrated. Find the corresponding P-value for this test..

The data in grams  are

     100.02 , 99.98 , 100.03

Answer:

The p-value is  [tex]p-value =0.5798[/tex]

Step-by-step explanation:

    Generally the sample mean of the given data is mathematically represented as

        [tex]\= x = \frac{100.02 + 99.98 + 100.03 }{3}[/tex]

        [tex]\= x =100.03 \ g[/tex]

Generally the standard deviation is mathematically represented as  

        [tex]s = \sqrt{\frac{\sum [x_i - \= x]^2 }{n-1} }[/tex]

=>     [tex]s = \sqrt{\frac{[ 100.02 - 100.01]^2+ [ 99.98 - 100.01]^2+[ 100.03 - 100.01]^2 }{3-1} }[/tex]

=>     [tex]s = 0.02645[/tex]

The null hypothesis is  [tex]H_o : \mu = 100[/tex]

The alternative hypothesis is  [tex]H_a : \mu \ne 100[/tex]

Generally the degree of freedom is mathematically represented as

            [tex]df = n - 1[/tex]

=>         [tex]df = 3 - 1[/tex]

=>         [tex]df = 2[/tex]

Generally the test statistics is mathematically represented as    

          [tex]t = \frac{\= x - \mu }{\frac{s}{\sqrt{n} } }[/tex]

=>      [tex]t = \frac{ 100.01 - 100 }{\frac{0.02645}{\sqrt{3} } }[/tex]  

=>      [tex]t = 0.655[/tex]

From the t distribution table the probability corresponding to the t  to the right of the bell curve  at a degree of freedom of  [tex]df = 2[/tex]

         [tex]P( T > 0.655 ) = 0.2899[/tex]

Generally the p-value for this two tailed test is mathematically represented as

          [tex]p-value = 2 * P(T > 0.655)[/tex]

=>       [tex]p-value = 2 * 0.2899[/tex]

=>       [tex]p-value =0.5798[/tex]

       

+) Evaluate the expression 81 – 82.
81 – 82 =

Answers

81 - 8^2 is 17 ..............

Answer:

81-8²

=81-(8×8)

=81-64

=17

The shortest route from London to York is 200 miles.
A lorry is expected to take 4 hours to travel this route.
The lorry actually travels by a different route which increases the distance by 20%, but it still arrives in 4 hours.
By how many more mph than the expected speed does the lorry travel?

Answers

Answer: The lorry is traveling 10 mph over the expected speed.

Step-by-step explanation:

If 200 miles takes 4 hours, the speed is 200mi/4hr which  is 50 mph.

If the distance is increased by 20%, the distance is 240 miles.

240mi/4hr = 60mph

The difference is 10mph

ndicate the answer choice that best completes the statement or answers the question.
Determine whether each table represents a linear or a nonlinear function.
by
3
4.5
1.5
2
16
16
V
14
18
Oa Nonlinear, As x increases by 1.5, y increases by a greater amount each time. The rate of change is not constant, so this function is
nonlinear
Ob. Linear; As x increases by 5, y increases by 4 each time. The rate of change is constant, so this function is linear.
Oc. Linear; As x increases by 5, y increases by 2 each time. The rate of change is constant, so this function is linear.
Od. Linear, As x increases by 1.5, y doubles each time. The rate of change is constant, so this function is linear.

Answers

A nonlinear is the correct answer

Rewrite 105,000 in scientific notation.

Answer options are in pic below

Answers

C is my chose of an answer

Answer:

the answer is the third option (C)

20 points! For students majoring in Hospitality Management, it was determined that 5% have visited 1–10 states, 16% have visited 11–20 states, 45% have visited 21–30 states, 19% have visited 31–40 states, and 15% have visited 41–50 states. Suppose a Hospitality Management student is randomly selected. What is the probability that the student has visited 21 or more states?

0.15
0.21
0.45
0.79

Answers

Answer:

So i feel like the answers is .79

Step-by-step explanation:

asking for the ones that visited 21 or more so thats .45+.19+.15=.79

Answer:

.55

Step-by-step explanation:

Find the unknown of the following

Answers

Step-by-step explanation:

For 4.

4b + 2b + 3b = 180°< Sum of angles of triangle >

9b = 180°

b = 180° / 9

b = 20°

4b = 4* 20° = 80°

2b = 2* 20° = 40°

3b = 3 * 20° = 60°

For 5.

x = 64° + 45° <Exterior angle of a triangle is equal to the sum of two opposite interior angles>

x = 109°

Hope it helps :)

There is 1 empty seat and 49 occupied seats on an airplane.What is the ratio of the number of empty seats to the number of occupied seats?

Answers

Step-by-step explanation:

This is a classic puzzle!

The answer is that the probability that the last person ends in up in his proper seat is exactly

1

2

The reasoning goes as follows:

First observe that the fate of the last person is determined the moment either the first or the last seat is selected! This is because the last person will either get the first seat or the last seat. Any other seat will necessarily be taken by the time the last guy gets to 'choose'.

Since at each choice step, the first or last is equally probable to be taken, the last person will get either the first or last with equal probability:

1

2

.

Sorry, no clue about a physical system

Garrett needs 3 gallons of fruit juice to make punch.

He already has 5/6 gallon of grape juice and 2/3 gallon of orange juice.

Drag amounts of juice that he can add to the juice he already has to make exactly 3 gallons.

Answers

Answer:

3 of each gallon

Step-by-step explanation:

It worked for me on ttm

Answer:

4 of 1/3 and 1 of 1/6

Step-by-step explanation:

5/6+2/3=9/6

9/6+4/3=17/6

17/6+1/6=18/6

18/6=3

The equation -7(u+3)=49 is solved in several steps below.
For each step, choose the reason that best justifies it

Answers

Answer:

u = -25/7

Step-by-step explanation:

-7(u + 3) = 4

-7u -21 = 4 (distribute the -7)

-7u = 25 (add 21 to get -7u by itself)

u = -25/7 (divide by -7 by both sides to find the value of u)

- 11/5 -2.4 1.6 15/10 - 2.25 in order from least to greatest

Answers

Answer (least to greatest):

-2.4-2.25-11/515/101.6

I hope this helps!

Answer:

1.6,- 11/5 ,2.25 , -2.4 15/10

Step-by-step explanation:

Can someone help me I appreciate it

Answers

150 degrees since 180 - 30 is 150

The integer 4 is considered all of the following except _____.

a term
a constant
an expression
a variable

Answers

Answer:

variable

Step-by-step explanation:

variables are often expressed by letters

Jacob is going on a vacation to Australia. His flight leaves at 1:15 P.M. It takes 1 hour to get to the airport, and Jacob wants to be at the airport 1 hour and 15 minutes before his flight leaves. What is the latest time that Jacob can leave for the airport?


Plzzzz help

Answers

Answer:

The latest time is 12:00

Step-by-step explanation:

take an hour away for 1:15 which is gonna be 12:15 then take the 15 minutes away and you get 12:00

Answer:

11:00

Step-by-step explanation:

if he leaves at 11:00 it’s takes an hour to get there. So when he gets there it’s 12:00 Add an hour 15 and you get 1:15

Please help answer the first 2 boxes for brainslt

> for brainslt

Answers

m- 2 b- 3 ... 2x+3 negative slope not sure if proportional or not
Answer:

1.
m=-3/2
b=3
Equation: -3/2x+3
Not sure what proportional is (I’m so srry)

And it will be a negative slope

2.
m= -2/5
b= 4
Equation is y= -2/5x+4
Again not sure what proportional means
It will be a negative slope as well

Step-by-step explanation:

Hope it helped!!
Other Questions
7th grade science , please dont get the answer from the internet :( Boy In The Bubble By Alec Benjamin.It was 6:48, I was walking homeStepped through the gate, and I'm all aloneI had chicken on the plate, but the food was coldThen I covered up my face so that no one knowsI didn't want trouble, I'm the boy in the bubbleBut then came troubleWhen my mom walked into the living roomShe said, "Boy, you gotta tell me what they did to you"I said, "You don't wanna know the things I had to do"She said, "Son, you gotta tell me why you're black and blue"I said I didn't want trouble, I'm the boy in the bubbleBut then came troubleAnd my heart was pumping, chest was screamingMind was running, air was freezingPut my hands up, put my hands upI told this kid I'm ready for a fightPunch my face, do it 'cause I like the painEvery time you curse my nameI know you want the satisfaction, it's not gonna happenKnock me out, kick me when I'm on the groundIt's only gonna let you downCome the lightning and the thunderYou're the one who'll suffer, sufferWell, I squared him up, left my chest exposedHe threw a quick left hook and it broke my noseI had thick red blood running down my clothesAnd a sick, sick look 'cause I like it thoughI said I didn't want trouble, I'm the boy in the bubbleBut then came troubleAnd my heart was pumping, chest was screamingMind was running, nose was bleedingPut my hands up, put my hands upI told this kid I'm ready for a fightPunch my face, do it 'cause I like the painEvery time you curse my nameI know you want the satisfaction, it's not gonna happenKnock me out, kick me when I'm on the groundIt's only gonna let you downCome the lightning and the thunderYou're the one who'll sufferIt was 6:48, he was walking homeWith the blood on his hands from my broken noseBut like every other day, he was scared to goBack to his house 'cause his pops was homeDrowning his troubles in whiskey bubblesJust looking for troubleWell, there's no excuse for the things he didBut there's a lot at home that he's dealing withBecause his dad's been drunk since he was a kidAnd I hope one day that he'll say to him"Put down those bubbles and that belt buckleIn this broken bubble"Punch my face, do it 'cause I like the painEvery time you curse my nameI know you want the satisfaction, it's not gonna happenKnock me out, kick me when I'm on the groundIt's only gonna let you downCome the lightning and the thunderYou're the one who'll suffer, suffer what should be done so that the expression 4+4 to the power of 2 - 52 will have a value of 10? Aaron earns a weekly salary of $350. He earns a 7% commission onthe sales that he makes. Last week his sales totaled $3200. who is the richest person in word which of the following substance is most likely basic Geneiva is looking for a document. She hasn't used this document in years, and yet it is still in Recent Documents. Which of the following best explains the this?A) She is experiencing a computer glitch that allows Recent Documents to retain all used documents. B) She has used fewer than nineteen other documents since the last document was last used.C) The document is pinned, and she is experiencing a computer glitch that allows Recent Documents to retain all used documents.D) The document is pinned, or she has not used nineteen documents since the document last was last used. Write a program to input a number and check whether it is divisible by 5 or not Plz help will mark brainliest :) If you dont know please dont answer its for a final(For both drop down menus) A. An evenB. An odd C. Neither an even nor an odd what was the myth of the Hessians during the Battle of Trenton plz help mee write your opinion A 90.00 g sample of Na, CO *xH, O is heated until all of the water is drivenoff, forming 32.28 g of the anhydrous salt, Na, Coz. What is the percent bymass of H,O in the hydrated compound, Na CO, *xH,O?* HELP HOW DO I SOLVE THIS Small and sprightly like a bantam hen is what type of figurative language? Andre is predicting the products of chemical reactions. In one reaction, a hydrocarbon is the only reactant. What is the best best prediction and explanation of the reaction? solve for x. x2-3[x-2]-4x= Explain what would happen to a figure if you transformed it using the rule(x-2,y+4). Then state whether the image would be similar, congruent, both, or neither. HELP PLEASE Completa las oraciones sobre las actividades que haca cadapersona de esta familia en un da de playa. Usa la forma correcta del verbo entre parntesis.Algunos parientes _______ en sus casasrodantes. (llegar) (WILL GIVE BRAINLIEST) Find the mean for the data shown below. Of what descent are the majority of French people? oAfrican and Indian oChinese and Greek oCeltic and Latino none of the above