There are 42 students in an elementary statistics class. On the basis of years of experience, the instructor knows that the time needed to grade a randomly chosen first examination paper is a random variable with an expected value of 5 min and a standard deviation of 6 min. (Give answers accurate to 3 decimal places.)
(a) If grading times are independent and the instructor begins grading at 6:50 P.M. and grades continuously, what is the (approximate) probability that he is through grading before the 11:00 P.M. TV news begins?
1
(b) If the sports report begins at 11:10, what is the probability that he misses part of the report if he waits until grading is done before turning on the TV?
2

Answer:

Option D is the correct option.

Step-by-step explanation:

Given: 3 boxes with volumes 1331 , 1331 , 729

To find : Height of stacked boxes

[tex]h {1}^{3} = 1331 = h1 = \sqrt[3]{1331} = 11[/tex]

[tex]h {2}^{3} = 1331 = h2 = \sqrt[3]{1331} = 11[/tex]

[tex]h {3}^{3} = 729 = h3 = \sqrt[3]{729} = 9[/tex]

Now,

[tex]h = h1 + h2 + h3[/tex]

[tex] = 11 + 11 + 9[/tex]

[tex] = 31[/tex]

Hope this helps...

Good luck on your assignment...

Answer:

T(n) = 5n + 20

Step-by-step explanation:

1 candy has a mass of 5 g.

n candies have a mass of 5n grams.

The box has a mass of 20 grams.

total mass = mass of candies + mass of box

T(n) = 5n + 20

n         T(n)

0           20

25         145

50         270

75          395

100        520

Answer:

395

Step-by-step explanation:

15.8=d/25

multiply both sides by 25 to remove the denominator

25×15.8=d

d=395

the answer is 36.36 but the closest to it is 37

Answer:

[tex]a^9 + b^ 5 + c^{13}[/tex]

Step-by-step explanation:

[tex](a^5 \times a^4)+(b^2 \times b^3) + (c^7 \times c^6)[/tex]

When bases are same and it is multiplication, then add the exponents.

[tex](a^{5+4})+(b^{2+3})+(c^{7+6})[/tex]

[tex](a^9)+(b^ 5) + (c^{13})[/tex]

Apply rule : [tex](a^b)=a^b[/tex]

[tex]a^9 + b^ 5 + c^{13}[/tex]

Answer:

[tex]a^9+b^5-c^{13[/tex]

Step-by-step explanation:

[tex](a^5*a^4) + (b^2*b^3)-(c^7*c^6)[/tex]

When bases are same, powers are to be added.

=> [tex](a^{5+4})+(b^{2+3})-(c^{7+6})[/tex]

=> [tex]a^9+b^5-c^{13[/tex]

Answer:

21.7

Step-by-step explanation:

When anything is 5 or above in a decimal place you round up to the next number for example

2.35 this would round up to be 2.4

21.65

Place value of 1 = ones place

Face value of 1 = 1

Note : The face value of a number will not change at all

Hope it helps you..If it's wrong plz say and I'll try to recorrect it :)

Answer:

$[58543.42; 73456.58]

Step-by-step explanation:

Hello!

For the variable

X: salary of a college graduate that took a statistics course

Out of n= 43 students, the calculated mean is [tex]\frac{}{X}[/tex]= $66000

The population standard deviation is δ= $18908

There is no information about the variable distribution, but since the sample size is big enough (n≥30), you can apply the CLT and approximate the distribution of the sample mean to normal [tex]\frac{}{X}[/tex]≈N(μ;σ²/n)

Then you can apply the approximation of the standard normal distribution to calculate the 99% CI

[tex]\frac{}{X}[/tex] ± [tex]Z_{1-\alpha /2}[/tex] * [tex]\frac{Singma}{\sqrt{n} }[/tex]

[tex]Z_{1-\alpha /2}= Z_{0.995}= 2.586[/tex]

[tex]\frac{Singma}{\sqrt{n} }= \frac{18908}{\sqrt{43} }= 2883.44[/tex]

[66000±2.586*2883.44]

$[58543.42; 73456.58]

With a 99% confidence level you'd expect that the interval $[58543.42; 73456.58] will include the average salary of college graduates that took a course of statistics.

I hope this helps!

Answer:  $323.33

Step-by-step explanation:

($17,000 + $4,900 - $2,500) ÷ 60 months = $323.33 per month

    ↓                ↓              ↓

 price        finance      down payment

Answer:

E[x] is larger

Step-by-step explanation:

I think E[x] is larger because the expected number of students on the bus of a randomly chosen student is larger.

This is because the higher the number of students present in a bus, the higher the probability that a randomly selected student would have been on that bus.

Whereas, for every driver to be chosen, the probability of any bus being chosen is 1/4 irrespective of the number of students in that particular bus

Answer:

A. y ≤ 1/2x + 2

Step-by-step explanation:

Well look at the graph,

It is a solid line with it shaded down,

meaning it is y ≤,

So we can cross out B. and D.

So the y intercept is 2, we know this because the y intercept is the point on the line that touches the y axis.

now the slope can be found by seeing how far away each points are from each other,

Hence, the answer is A. y ≤ 1/2x + 2

Answer:

The null hypothesis is ;

H0 ≥ 12

While the alternative hypothesis H1 is ;

H1 < 12

Step-by-step explanation:

Here, we want to correctly identify the null hypothesis H0 and the alternative hypothesis H1

The null hypothesis is as follows ;

H0 ≥ 12

While the alternative hypothesis H1 is ;

H1 < 12

Answer:

10

Step-by-step explanation:

To find 20% of 50 you need to times 20 with 50 and divide by 100.

20×50÷100

=10

Answer: B

Step-by-step explanation:

Answer:B

Step-by-step explanation: I took the edge quiz and it was right.

Answer:

Quantity (lbs) of type 1 candy  x = 8

Quantity (lbs) of type 2 candy  y = 17,5

Step-by-step explanation:

Let´s call  "x" quantity (in pounds) of candy type 1 in the mixture, and "y" quantity (in pounds ) of candy type 2, then according to the problem statement.

x  +  y  =  25,5

2,20*x  +  7,30*y = 5,70 * 25,5   ⇒  2,20*x  +  7,30*y = 145,35

Then we have a two equation system

x  +  y  =  25,5                                   ⇒   y = 25,5 - x

2,20*x  +  7,30*y = 145,35               ⇒ 2,20*x + 7,30* (25,5 - x ) = 145,35

2,20*x + 186,15 - 7,30*x = 145,35

5,1*x  = 40,8

x = 40,8/5,1

x = 8 lbs

And   y  =  25,5 - 8

y = 17,5 lbs

Answer: 0.06x

Step-by-step explanation:

The given statement:  A number is 30% of 20% of the number x.

The required algebraic expression would be:

30% of 20% of x

[tex]=\dfrac{30}{100}\times \dfrac{20}{100}\times x[/tex]  [we divide a percentage by 100 to convert it into decimal]

[tex]=\dfrac{6}{100}\times x\\\\=0.06x[/tex]

Hence, the required algebraic expression would be :

0.06x

Answer:

Step-by-step explanation:

Hello, because of the end behaviour it means that the leading coefficient is negative so we can construct such polynomial function as below.

[tex]\large \boxed{\sf \bf \ \ -(x+7)(x-6) \ \ }[/tex]

Hope this helps.

Do not hesitate if you need further explanation.

Thank you

The polynomial function will be f ( x ) = - x² - x + 42

What is Quadratic Equation?

A quadratic equation is a second-order polynomial equation in a single variable x , ax²+ bx + c = 0. with a ≠ 0. Because it is a second-order polynomial equation, the fundamental theorem of algebra guarantees that it has at least one solution. The solution may be real or complex.

Given data ,

The polynomial function is of second degree with zeros of -7 and 6

So , x = -7 and x = 6

Let the function be f ( x ) where f ( x ) = ( x + 7 ) ( x - 6 )

Now , as x tends to infinity , the negative makes no such difference on the zeros of the function f ( x ) ,

And , f ( x ) = - ( x + 7 ) ( x - 6 )

Therefore , to find the polynomial function , f ( x ) = - ( x + 7 ) ( x - 6 )

f ( x ) = - [ x² - 6 x + 7 x - 42 ]

        = - [ x² + x - 42 ]

        = - x ² - x + 42

Hence , the polynomial function f ( x ) = - x ² - x + 42

To learn more about polynomial function click :

https://brainly.com/question/25097844

#SPJ2

Answer:

.15* house price = 28,500

house price = 28,500 / .15

house price =  190,000

Step-by-step explanation:

Answer: 190,000

Step-by-step explanation:

the equation looks like this - .15x=28,500. then you divide both sides by .15 and get x=190,000

If it has a single zero that means it has to be just touching the x-axis with its tip.

We know that if it has only one zero, the discriminant equals 0.

So,

[tex]D=b^2-4ac=0\implies (-k)^2-4(1)(9)=0[/tex]

Solving for k,

[tex]k=\pm\sqrt{36}=\boxed{\pm{6}}[/tex].

Hope this helps.

Answer:

5/12

Step-by-step explanation:

Total number of marbles in the bag

6red+ 4blue + 14 yellow = 24 marbles

Not yellow marbles = 10 marbles

P ( not yellow ) = number of not yellow marbles / total marbles

                          =10/24

                          = 5/12

Answer:

5/12

Step-by-step explanation:

6 red marbles

4 blue marbles

14 yellow marbles

total marbles = 6 + 4 + 14 = 24 marbles

24 - 14 = 10 marbles

10 marbles are not yellow.

P(not yellow) = 10/24 = 5/12

Answer:

viscosity is the state of being thick, sticky, and semifluid in consistency, due to internal friction.

"cooling the fluid raises its viscosity"

a quantity expressing the magnitude of internal friction, as measured by the force per unit area resisting a flow in which parallel layers unit distance apart have unit speed relative to one another.

plural noun: viscosities

"silicone oils can be obtained with different viscosities"

Step-by-step explanation:

The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. hope this helps you :)

Answer:

O An oil's resistance to flow at different temperatures

Step-by-step explanation:

Internal friction of a moving fluid .

Answer:

A) 22 cans required to paint

B) Including 13% tax, cost of painting = $633.93

Step-by-step explanation:

As we check the figure, we have a composite figure.

Cuboid on the base and a pyramid on the top of it.

To find the area to be painted, we have 4 rectangular faces of cuboid with dimensions 6m [tex]\times[/tex] 3m.

And 4 triangular faces of pyramid with Base = 6m and Height 5m.

So, total area to be painted = 4 rectangular faces + 4 triangular faces

Area of rectangle = Length [tex]\times[/tex] Width = 6 [tex]\times[/tex] 3 = 18 [tex]m^2[/tex]

Area of triangle = [tex]\frac{1}{2}\times Base \times Height =\frac{1}{2}\times 6 \times 5 = 15\ m^{2}[/tex]

Total area to be painted = 4 \times 18 + 4 \times 15 = 72 + 60 = 132 [tex]m^2[/tex]

A) Area painted by 1 can = 6 [tex]m^2[/tex]

Cans required to paint 132 [tex]m^2[/tex] = [tex]\frac{132}{6} = 22\ cans[/tex]

B)

Cost of 1 can = $25.50

Cost of 22 can = $25.50 [tex]\times[/tex] 22 = $561

Including tax of 13% = $561 + $561 [tex]\times \frac{13}{100}[/tex] = $561 + $72.93 = $633.93

So, the answers are:

A) 22 cans required to paint

B) Including 13% tax, cost of painting = $633.93

Answer

Step-by-step explanation:

Given,

r = 10

Let's create an equation,

[tex]3r = 10 + 5s[/tex]

plugging the value of r

[tex]3 \times 10 = 10 + 5s[/tex]

Multiply the numbers

[tex]30 = 10 + 5s[/tex]

Move 5s to L.H.S and change its sign

Similarly, Move 30 to R.H.S and change its sign.

[tex] - 5s = 10 - 30[/tex]

Calculate

[tex] - 5s = - 20[/tex]

The difference sign ( - ) should be cancelled on both sides

[tex]5s = 20[/tex]

Divide both sides of the equation by 5

[tex] \frac{5s}{2} = \frac{20}{5} [/tex]

Calculate

[tex]s = 4[/tex]

The value of s is 4.

Hope this helps..

Best regards!!

Answer:

A. 4 (on edgenuity)

Step-by-step explanation:

Answer:

(D) -2,-3

Step-by-step explanation:

From the origin, we can find the current position of point B by counting.

B is 2 to the left of the y-axis, meaning that it's x value is -2.

B is 3 down of the x-axis, making it's y value -3.

Therefore, the coordinates of point B are -2,-3.

Hope this helped!

Answer: (D) -2,-3

Step-by-step explanation:

Hey there! I'm happy to help!

Let's set this up a system of equations where x represents the number of 10 dollar bills and y represents the number of 20 dollar bills.

10x+20y=440

x=y+2

We see that x has a value of y+2, so we can replace the x in the first equation with y+2 so we can solve for y.

10(y+2)+20y=440

We use distributive property to undo the parentheses.

10y+20+20y=440

We combine like terms.

30y+20=440

We subtract 20 from both sides.

30y=420

y=14

Since there are 2 more $10 bills, there would be 16 of those.

Therefore, there are 16 $10 bills and 14 $20 bills.

Have a wonderful day! :D

Answer:

26

Step-by-step explanation:

Given that:

At time, t=0, Billy puts 625 into an account paying 6% simple interest

At the end of year 2, George puts 400 into an account paying interest at a force of interest, 1/(6+t), for all t ≥ 2.

If both accounts continue to earn interest indefinitely at the levels given above, the amounts in both accounts will be equal at the end of year n. Calculate n.

In order to calculate n;

Let K constant to be the value of time for both accounts

At  time, t=0, the value of time K when Billy puts 625 into an account paying 6% simple interest is:

[tex]K = 625 \times (1+ 0.06 K)[/tex]

[tex]K = 625 +37.5 K[/tex]

At year end 2; George  amount of 400 will grow at a force interest, then the value of  [tex]K = 400 \times e^{\int\limits^2_k {\dfrac{1}{6+t}} \, dx }[/tex]

[tex]K =400 \times \dfrac{6+K}{6+2}[/tex]

[tex]K =400 \times \dfrac{6+K}{8}[/tex]

[tex]K =50 \times ({6+K})[/tex]

[tex]K =300+50K[/tex]

Therefore:

If K = K

Then:

625 + 37.5 = 300 +50 K

625-300 = 50 K - 37.5 K

325 = 12.5K

K = 325/12.5

K = 26

the amounts in both accounts  at the end of year n = K = 26

Answer:

x=2 y=4

Step-by-step explanation:

Answer:

45 min

Step-by-step explanation:

Here,

the we take the work as W and Alan's speed as A and Zack's speed as Z.

A = 2Z

W = 30 ( A+Z)

if the time for Alan to done cleaning alone is t then t = W ÷ A

t = ( 30 (A+(A÷2)))÷ A

t = 45 min

I am done .

Answer:

90º

Step-by-step explanation:

just look at where 31º on the right lines up with the value on the left (aka around 90º)

Answer:

87.8 °F ≈ 90°F

Step-by-step explanation:

[tex]x \ degrees \ F = 31 \ degree \ Celsius *\frac{9}{5} + 32\\x \ degrees \ F = 55.8 + 32\\\\x \ degrees \ Fahrenheit = 87.8 \ degrees \ Farenheit[/tex]

Answer:

The answer is below

Step-by-step explanation:

Given that mean (μ) of 32.9 seconds and a standard deviation (σ) of 6.4 seconds.

The z score is used to measure by how many standard deviation the raw score is above or below the mean. It is given by:

[tex]z=\frac{x-\mu}{\sigma}\\[/tex]

a) For x < 33.2 seconds

[tex]z=\frac{x-\mu}{\sigma}\\\\z=\frac{33.2-32.9}{6.4} =0.05[/tex]

From the normal distribution table, the probability that a randomly chosen student completes the activity in less than 33.2 seconds = P(x < 33.2) = P(z < 0.05) = 0.5199 = 51.99%

b) For x > 46.6 seconds

[tex]z=\frac{x-\mu}{\sigma}\\\\z=\frac{46.6-32.9}{6.4} =2.14[/tex]

From the normal distribution table,  the probability that a randomly chosen student completes the activity in more than 46.6 seconds = P(x > 46.6) = P(z > 2.14) = 1 - P(z < 2.14) = 1 - 0.9927 = 0.0073 = 0.73%

c) For x = 35.5 seconds

[tex]z=\frac{x-\mu}{\sigma}\\\\z=\frac{35.5-32.9}{6.4} =0.41[/tex]

For x = 42.8 seconds

[tex]z=\frac{x-\mu}{\sigma}\\\\z=\frac{42.8-32.9}{6.4} =1.55[/tex]

From the normal distribution table, the proportion of students take between 35.5 and 42.8 seconds to complete the activity = P(35.5 < x < 42.8) = P(0.41< z< 1.55) = P(z < 1.55) - P(z < 0.41) = 0.9332 - 0.6591 = 0.2741 = 27.41%

d) A probability of 75% = 0.75 corresponds to a z score of 0.68

[tex]z=\frac{x-\mu}{\sigma}\\\\0.68=\frac{x-32.9}{6.4} \\\\x-32.9=4.4\\x=4.4+32.9\\x=37.3[/tex]

75% of all students finish the activity in less than 37.3 seconds