The amount of time (in minutes per day) spent on social media for a sample of 10 teens has a mean of 186.7 and a sample standard deviation of 19.99. An independent sample of 8 older adults has a mean of 93.5 minutes with a sample standard deviation of 32.01. Assume that the time spent on social media is approximately normally distributed for each group. a) Determine the value of the test statistic to test H subscript 0 colon space mu subscript t e e n end subscript equals mu subscript o l d e r end subscript against H subscript A colon space mu subscript t e e n end subscript not equal to mu subscript o l d e r end subscript. b) Determine the p-value or critical value for this test at alpha equals 0.05. c) What is your conclusion about whether the two age groups spend the same average amount of time on social media

Answer:

i think the answer is 12 and 18

Answer:

For Q. 17 I believe it's "the function has a minimum at -1" take this answer with a grain of salt but the other three seem to be true and I don't know how to solve this one so I'm assuming it's the false one.

Answer:

A or g(x) = f(x − 3) + 3

Step-by-step explanation:

Answer:

It is 603 units greater

Step-by-step explanation:

Given

See attachment for table

Average rate of change over (a,b) is calculated as:

[tex]Rate = \frac{f(b) - f(a)}{b-a}[/tex]

For interval [7,9], we have:

[tex][a,b] = [7,9][/tex]

So, we have:

[tex]Rate = \frac{f(9) - f(7)}{9-7}[/tex]

[tex]Rate = \frac{f(9) - f(7)}{2}[/tex]

From the table:

[tex]f(9) = 3878[/tex]

[tex]f(7) = 1852[/tex]

So:

[tex]Rate = \frac{f(9) - f(7)}{2}[/tex]

[tex]Rate = \frac{3878 - 1852}{2}[/tex]

[tex]Rate = \frac{2026}{2}[/tex]

[tex]Rate = 1013\\[/tex]

For interval [4,6], we have:

[tex][a,b] = [4,6][/tex]

So, we have:

[tex]Rate = \frac{f(6) - f(4)}{6-4}[/tex]

[tex]Rate = \frac{f(6) - f(4)}{2}[/tex]

From the table:

[tex]f(6) = 1178[/tex]

[tex]f(4) = 358[/tex]

So:

[tex]Rate = \frac{f(6) - f(4)}{2}[/tex]

[tex]Rate = \frac{1178 - 358}{2}[/tex]

[tex]Rate = \frac{820}{2}[/tex]

[tex]Rate = 410[/tex]

Calculate the difference (d) to get how much greater their rate of change is:

[tex]d = 1013 - 410[/tex]

[tex]d = 603[/tex]

Answer:

603

Step-by-step explanation:

i took it

The standard deviation of the distribution is 1.08.

Option B is the correct answer.

The standard deviation measures how spread out the data is from the mean, and it is a measure of the average distance of the data points from the mean.

We have,

To find the standard deviation of the distribution, we first need to calculate the expected value (mean) of X.

The expected value of X is:

E(X) = (4)(0.4) + (3)(0.32) + (2)(0.17) + (1)(0.08) + (0)(0.03)

= 1.6 + 0.96 + 0.34 + 0.08 + 0

= 2.98

Next, we need to calculate the variance of X:

Var(X) = (4 - 2.98)²(0.4) + (3 - 2.98)²(0.32)

+ (2 - 2.98)²(0.17) + (1 - 2.98)²(0.08) + (0 - 2.98)²(0.03)

= 0.64(0.4) + 0.0004(0.32) + 0.7921(0.17) + 5.4084(0.08) + 8.6404(0.03)

= 0.256 + 0.000128 + 0.134257 + 0.432672 + 0.259212

= 1.082

The standard deviation of X is the square root of the variance:

So,

SD(X) = √(Var(X))

= √(1.082)

= 1.04 (approximately)

Thus,

The standard deviation of the distribution is 1.08.

Learn more about standard deviation here:

brainly.com/question/23907081

#SPJ7

Answer:

Step-by-step explanation:

2x+10x=12x

12x=-21

x=-1.75

Answer:

x=-7,-3

Step-by-step explanation:

x2+10x+21

(x+7)(x+3)

x=-7,-3

Answer:

a) The value of q is 0.2.

b) E(X) = 1.85.

Step-by-step explanation:

Question a:

The sum of all the probabilities must be 1. So

[tex]0.3 + x + 0.1 + 0.15 + 0.25 = 1[/tex]

[tex]x + 0.8 = 1[/tex]

[tex]x = 0.2[/tex]

The value of q is 0.2.

Question b:

Multiplication of each value of x by its probability. So

[tex]E(X) = 0*0.3 + 1*0.2 + 2*0.1 + 3*0.15 + 4*0.25 = 1.85[/tex]

So the answer is E(X) = 1.85.

Answer:

(0.25 ; 21.75)

8.7 (1 decimal place)

Step-by-step explanation:

Net change in scores : X = 6,14,12,23,0

Sample mean, xbar = (6 + 14 + 12 + 23 + 0) /5 = 55 /5 = 11

Sample standard deviation, s = 8.66 ( from calculator)

Sample standard deviation = 8.7( 1 decimal place)

Sample size, n = 5

The 95% confidence interval; we use t, because n is small

Tcritical at 95%, df = 4 - 1 = 3 ; Tcritical = 2.776

Xbar ± standard Error

Standard Error = Tcritical * s/√n

Standard Error = 2.776 * 8.66/√5

Standard Error = 10.751086 = 10.75

Lower boundary = (11 - 10.75) = 0.25

Upper boundary = (11 + 10.75) = 21.75

(0.25 ; 21.75)

The

Answer:

The cost for 4 snacks is 18 dollars.

Cost for x snacks: 4.5x

Step-by-step explanation:

4 x 4.5 = 18

Answers:

The algebraic expression shown above is the same as writing 52+4.50x

You may not need to type in "dollars" or a dollar sign, as your teacher may just want the numbers and algebraic symbols.

=====================================================

Explanation:

There are four people going to the movies, and each ticket costs $13 a piece, so that means the total so far is 4*13 = 52 dollars.

If we want to include snacks, then it costs $4.50 per snack. Buying 4 packages will cost an additional 4.50*4 = 18 dollars. In total, if Kiran wants to buy four snacks, then he'll need 52+18 = 70 dollars.

---------------------

Instead of computing 4.50*4 to get 18, we can leave the "4.50*4" like it is. Adding it onto the 52 found earlier leads to the expression 52+4.50*4

Now imagine that instead of "4", we just had a generic placeholder x take over. The x is standing in for any positive real number, or it could stand in for 0 if Kiran decides to not buy any snacks at all.

If we replace that "4" with x, then the expression

52+4.50*4

is the same as

52+4.50*x

Often times, you'll see the multiplication symbol omitted and the expression could look like 52+4.50x

Because we can add two numbers in any order, that expression above is the same as 4.50x+52

-------------------

Extra info (optional section):

The useful thing about something like 4.50x+52 is that we can graph y = 4.50x+52 and/or set up a table to be able to quickly determine how much money it will cost for buying any amount of snacks.

For example, let's say he wants to buy 10 snacks. That means we replace x with 10 and evaluate like so

4.50x+52 = 4.50*10+52 = 45+52 = 97

Buying 10 snacks, on top of the 4 movie tickets, cost $97 in total.

Answer:

Suppose the one number be x

And the other number be 6x

The sum of two numbers is 5

x+6x=5

7x=5

X=5/7

Therefore

One number be 5/7

And other number be 6 * 5/7=30/7

If you are helped with my answer pls tag me brianliest I really want it

THANK YOU...............

9514 1404 393

Answer:

  C. 6 > 3

Step-by-step explanation:

It is true that 6 is greater than 3.

__

All negative numbers are less than any positive numbers.

We hope you are sufficiently familiar with numbers and counting to be able to tell which positive numbers are more or less than any other positive number.

Answer:

the formula for finding cone volume is V=πr²× 1/3

Step-by-step explanation:

230=3.14×x²×1/3

we have to solve for X that is our radius

14.8

Answer:

y = 48°

Step-by-step explanation:

The value of an inscribed angle is half the value of the arc it subtends.

The angle marked x subtends the arc marked 66°, so has a value of ...

x = 66°/2

x = 33°

The value of y is similarly found.

y = 96°/2

y = 48°

The angle marked with a dot is an external angle of the triangle, so is the sum of the remote internal angles, x and y:

dot angle = x + y = 33° +48° = 81°

Of course, angle z is the supplement of this:

z = 180° -81°  

z = 99°

Answer::112

Step-by-step explanation:

Answer:

180°

Step-by-step explanation:

it's half of a circle

The angle AXG is a straight line. The measure of a straight line would be 180

The measure is 180

Answer:

c- use 1.0 as an estimate

Step-by-step explanation:

9514 1404 393

Answer:

  A, F

Step-by-step explanation:

Points A(-1, 0) and F(-3, 8) lie on the 2nd line. (Its equation is 4x+y=-4.)

Answer:

The answer should be $57000(1.025)²⁰ = $93,401

Step-by-step explanation:

Answer:

Jenelle invested $ 13,000 in Fund A and $ 4,000 in Fund B.

Step-by-step explanation:

Given that Jenelle invested $ 17000 in two mutual funds, and Fund A earned 4% profit during the first year, while Fund B suffered a 1.5% loss, if she received a total of $ 460 profit, to determine how much had she invested in each mutual fund, the following calculation must be performed:

17000 x 0.04 - 0 x 0.015 = 680

15000 x 0.04 - 2000 x 0.015 = 570

10,000 x 0.04 - 7000 x 0.015 = 295

12500 x 0.04 - 4500 x 0.015 = 432.5

13000 x 0.04 - 4000 x 0.015 = 460

Therefore, Jenelle invested $ 13,000 in Fund A and $ 4,000 in Fund B.

Answer: Graph D

Step-by-step explanation: Got it right on plato

The graph of a function with the same amplitude as m(x) is graph D.

The general cosine function is written as:

f(x) = A*cos(kx) + M

Where A is the amplitude, k is the angular frequency, and M is the midline.

In our case:

m(x) = -2*cos(x+π).

The amplitude is -2, which means that the distance between a peak and a trough must be twice the absolute value of the amplitude:

2*|-2| = 4

With this in mind, the only graph that meets this requirement is the graph D.

If you want to learn more about cosine functions, you can read:

https://brainly.com/question/7872492

Answer:

[tex]x = 55°[/tex]

Step-by-step explanation:

L1 and L2 are parallel, so that the 2 interior angles are equal to 180°.

[tex](2x + 10) + (x + 5) = 180° \\ 2x + x + 10 + 5 = 180° \\ 3x = 165° \\ x = 55°[/tex]

Answer:

translation

Step-by-step explanation:

Answer:

I think it's dilation or none

Step-by-step explanation:

Answer:

Step-by-step explanation:

1). Given equation is,

   2x² - 3x = 6

   2x² - 3x - 6 = 0

   To find the solutions of the equation we will use quadratic formula,

   x = [tex]\frac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]

   Substitute the values of a, b and c in the formula,

   a = 2, b = -3 and c = -6

   x = [tex]\frac{3\pm\sqrt{(-3)^2-4(2)(-6)}}{2(2)}[/tex]

   x = [tex]\frac{3\pm\sqrt{9+48}}{4}[/tex]

   x = [tex]\frac{3\pm\sqrt{57}}{4}[/tex]

   x = [tex]\frac{3+\sqrt{57}}{4},\frac{3-\sqrt{57}}{4}[/tex]

   Therefore, there are two real solutions.

2). Given equation is,

    x² + 1 = 2x

    x² - 2x + 1 = 0

    (x - 1)² = 0

     x = 1

     Therefore, there is one real solution of the equation.

3). 2x² + 3x + 2 = 0

     By applying quadratic formula,

     x = [tex]\frac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]

      x = [tex]\frac{-3\pm\sqrt{3^2-4(2)(2)}}{2(2)}[/tex]

      x = [tex]\frac{-3\pm\sqrt{9-16}}{4}[/tex]

      x = [tex]\frac{-3\pm i\sqrt{7}}{4}[/tex]

      x = [tex]\frac{-3+ i\sqrt{7}}{4},\frac{-3- i\sqrt{7}}{4}[/tex]

      Therefore, there are two complex (non real) solutions.

Answer:

1. Obtuse angle

2. 5

3. 117

Step-by-step explanation:

1. Any angle that is wider than 90 degrees is obtuse.

2. 180 = straight angle so, 180-140=40 8x5=40 so x=5

3. Supplementary angles are one angle that is 180 so, 180-63= 117

Answer:

x = 9

Step-by-step explanation:

4(5 + 4) = 3(x + 3) => Intersecting secants theorem

4(9) = 3(x + 3)

Open bracket by applying distributive property

36 = 3x + 9

Subtract 9 from each side

36 - 9 = 3x + 9 - 9

27 = 3x

Divide both sides by 3

27/3 = 3x/3

9 = x

x = 9

Answer:

(5x+7) (5x-7)

Step-by-step explanation:

you can look up the answer on symbolab if needed