Erythropoietin (EPO) is a banned drug used by athletes to increase the oxygen-carrying capacity of their blood. New tests for EPO were first introduced prior to the 2000 Olympic Games held in Sydney, Australia. Chance (Spring 2004) reported that of a sample of 830 world-class athletes, 159 did not compete in the 1999 World Championships (a year prior to the new EPO test). Similarly, 133 of 82:5 potential athletes did not compete in the 2000 Olympic Games. Was the new test effective in deterring an athlete's participation in the 2000 Olympics? If so, then the proportion of nonparticipating athletes in 2000 will be greater than the proportion of nonparticipating athletes in 1999, Use a 98% confidence interval to compare the two proportions and make the proper conclusion.

Answer:

The solution to the equation is (8,13).

Step-by-step explanation:

A linear system of equations is composed by two lines.

The solution of the system is the point where the two lines intersect, that is.

In this question:

Point of intersection (8,13).

So

The solution to the equation is (8,13).

Answer:

The common ratio is 4

Step-by-step explanation:

To find the common ratio take the second term and divide by the first term

-20/-5 = 4

To verify take the third term and divide by the second

-80/-20 = 4

The common ratio is 4

Answer:

4

Step-by-step explanation:

To find the common ratio, divide one term by the term before it.

-20 ÷ -5 = 4

-80 ÷ -20 = 4

Each number is multiplied by 4 to get to the next number.

I hope this helps :))

Answer:

A=450

Step-by-step explanation:

A=a+b

2h=12+33

2·20=450

Answer:

Area=450

Step-by-step explanation:

[tex]a+b/2h[/tex]

Answer:

[tex] 25.5 -3.3= 22.2[/tex]

[tex] 25.5 +3.3= 28.8[/tex]

And the confidence interval would be given by: [tex] 22.2\leq \mu \leq 28.8[/tex]

Step-by-step explanation:

[tex]\bar X=25.5[/tex] represent the sample mean for the sample  

ME= 3.3 represent the margin of error

Confidence interval

The confidence interval for the mean is given by the following formula:

[tex]\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}[/tex]   (1)

The margin of error is given by;

[tex] ME =t_{\alpha/2}\frac{s}{\sqrt{n}}= 3.3[/tex]

And the confidence interval would be given by:

[tex] 25.5 -3.3= 22.2[/tex]

[tex] 25.5 +3.3= 28.8[/tex]

And the confidence interval would be given by: [tex] 22.2\leq \mu \leq 28.8[/tex]

Answer:

15 baskets

Step-by-step explanation:

Answer:

9

Step-by-step explanation:

[tex]2x+3y=36\\\\2x+3(6)=36\\\\2x+18=36\\\\2x=18\\\\x=9[/tex]

Hope this helps!

Answer:

X= 9

Step-by-step explanation:

2x+3y=36

2x+3(6)=36

2x+18=36

    -18  -18

2x=18

----------

   2

x=9

5×4=20 is closer to 24.9344.

[tex]487 \times 512=24.9344[/tex]

Let's try placing the decimals after the hundreds place.

[tex]4.87 \times 5.12=24.9344[/tex]

It works.

There is more than one possibility.

[tex].487 \times 51.2=24.9344[/tex]

[tex]48.7 \times .512=24.9344[/tex]

Step-by-step explanation:

Find the lowest common multiple of 15 and 12.

Which is 60.

15×4=60 so 32x4=£1.28

12x5=60 so 43x5=£2.15

2.15+1.28= £3.43

Answer:

The box has sides of 11.07 cm and height of 3.69 cm.

The cost (minimum) is 147 cents per box.

Step-by-step explanation:

We have a box with open top, with a volume of 452 cm^3.

Let x: base side of the box, in cm, and y: height of the box, in cm.

Then, the volume can be expressed as:

[tex]V=x^2\cdot y=452\\\\y=452x^{-2}[/tex]

This box has 4 sides and 1 base. The material cost is 0.4 cents/cm^2 for the base and 0.6 cents/cm^2 for the sides.

Then, we can write the cost as:

[tex]C=0.4\cdot 1\cdot (x^2)+0.6\cdot 4\cdot (xy)\\\\\\xy=x\cdot(452x^{-2})=452x^{-1}\\\\\\C=0.4x^2+2.4(452x^{-1})\\\\\\C=0.4x^2+1084.8x^{-1}[/tex]

The value for x that gives a minimum cost can be found deriving the function C and equal to 0:

[tex]\dfrac{dC}{dx}=0.4(2x)+1084.8(-1\cdot x^{-2})=0\\\\\\0.8x-1084.8x^{-2}=0\\\\0.8x=1084.8x^{-2}\\\\0.8x^{1+2}=1084.8\\\\x^3=1084.8/0.8=1356\\\\x=\sqrt[3]{1356}\\\\x=11.07[/tex]

The height can be calculated with the equation:

[tex]y=452x^{-2}=452(11.07^{-2})=452\cdot 0.00816 =3.69[/tex]

The minimum cost can be calculated as:

[tex]C=0.4x^2+1084.8x^{-1}\\\\C(11.07)=0.4(11.07)^2+1084.8(11.07)^{-1}\\\\C(11.07)=0.4\cdot 122.51+1084.8\cdot0.09\\\\C(11.07)=49+98\\\\C(11.07)=147[/tex]

Answer:

4x -8 +4y

Step-by-step explanation:

Distribute

4(x – 2 + y)

4*x -4*2 +4*y

4x -8 +4y

Answer:

x = 20

Step-by-step explanation:

The sum of the three angles in the diagram is 180 degrees since they form a straight line

x + 100 + 3x = 180

Combine like terms

100 +4x = 180

Subtract 100 from each side

100+4x-100 =180-100

4x= 80

Divide each side by 4

4x/4 = 80/4

x = 20

Answer:

36

Step-by-step explanation:

11*11=4

(1+1)*(1+1)=4

2 * 2 = 4

22*22=16

(2+2)*(2+2)=16

4 * 4 = 16

33*33=?

(3+3)*(3+3)=?

6 * 6 = 36

So the answer is 36

Series: 4, 16, 36

Answer: The answer is 36 :)

hope that helped

Answer:

  a = (d -c)/b

Step-by-step explanation:

Undo the addition of c, by subtracting c.

  ab +c -c = d -c

  ab = d - c

Undo the multiplication by b, by dividing by b.

  ab/b = (d -c)/b

  a = (d -c)/b

Answer:

27 stuffed bears

Step-by-step explanation:

Erin: 55   Su: 15

Erin: 55-7=48 ( 7 will be kept for herself)

Erin and her sisters: 48/4= 12

Each sister besides Erin and Su have 12

Su: 15+12=27

Thus, Su will have 27 stuffed bears

Answer:

31 Stuffed Bears

Step-by-step explanation:

55 - 7 = 48

48 / 3 = 16

16 + 15 = 31

Sue has 31 stuffed bears

Answer:

the area of the circle is 102.11 square metres

Answer:

17.85 feet.

Step-by-step explanation:

Area = 1/4 * 3.14 * r^2  where r is the radius

So r^2 = 19.625 / (1/4 * 3.14)

r^2 = 25

r = 5 feet.

The perimeter = 2r + 1/4 * 2* 3.14*r

= 2*5 + 7.85

= 17.85 feet.

Answer:

There were 210 downloads of the standard version.

Step-by-step explanation:

This question can be solved using a system of equations.

I am going to say that:

x is the number of downloads of the standard version.

y is the number of downloads of the high-quality version.

The size of the standard version is 2.6 megabytes (MB). The size of the high-quality version is 4.2 MB. The total size downloaded for the two versions was 4074 MB.

This means that:

[tex]2.6x + 4.2y = 4074[/tex]

Yesterday, the high-quality version was downloaded four times as often as the standard version.

This means that [tex]y = 4x[/tex]

How many downloads of the standard version were there?

This is x.

[tex]2.6x + 4.2y = 4074[/tex]

Since [tex]y = 4x[/tex]

[tex]2.6x + 4.2*4x = 4074[/tex]

[tex]19.4x = 4074[/tex]

[tex]x = \frac{4074}{19.4}[/tex]

[tex]x = 210[/tex]

There were 210 downloads of the standard version.

Answer:

68°

Step-by-step explanation:

Angle IJK is 112

Opposite angles of a quadrilateral inscribed in a circle add up to 180°

So

m<IHK = 180-112

m<IHK = 68°

Answer:

(a)[tex]\dfrac{11}{26}[/tex]

(b)[tex]\dfrac{9}{13}[/tex]

(c)[tex]\dfrac{4}{13}[/tex]

Step-by-step explanation:

Number of cards in a Standard Deck=52

(a)

Number of Diamonds (D)=13

Number of Face Cards(F) = 12

Number of Diamonds that are face cards = 3

[tex]Pr($that the card is a diamond or a face card)=P(D)+P(F)-P(D \cap F)\\=\dfrac{13}{52} +\dfrac{12}{52} -\dfrac{3}{52} \\=\dfrac{22}{52} \\=\dfrac{11}{26}[/tex]

(b)The probability that the card is neither an ace nor a heart.

Number of Aces (A)=4

Number of Hearts(H) = 13

Number of Hearts that are Aces = 1

[tex]Pr($that the card is a Ace or a Heart), P(A \cup H)=P(A)+P(H)-P(A \cap H)\\=\dfrac{4}{52} +\dfrac{13}{52} -\dfrac{1}{52} \\=\dfrac{16}{52} \\$Therefore, probability that the card is neither an ace nor a heart.\\=1-P(A \cup H)\\=1-\dfrac{16}{52}\\=\dfrac{36}{52}\\=\dfrac{9}{13}[/tex]

(c)The probability that the card is a face card or a 3

Number of 3 cards(T)=4

Number of Face Cards(F) = 12

[tex]Pr($that the card is a three or a face card)=P(T)+P(F)\\=\dfrac{4}{52} +\dfrac{12}{52} \\=\dfrac{16}{52} \\=\dfrac{4}{13}[/tex]

Answer:

3,380 combinations

Step-by-step explanation:

26*5*26= 3,380

Answer:

3380

Step-by-step explanation:

Since there are 26 letters, it would be

26*5*26

This is 3380

Answer:  The correct answer is:  " 2x² " .

________________________________

Step-by-step explanation:

________________________________

We are asked:  "What is the sum of:  "x + x² + 2" and "x² − 2 − x" ?

Since we are to find the "sum" ;

  →  We are to "add" these 2 (two) expressions together:

     →     (x + x² + 2) +  (x² − 2 − x) ;

Note:  Let us rewrite the above, by adding the number "1" as a coefficient to:  the values "x" ; and "x² " ;  since there is an "implied coefficient of "1" ;

            → {since:  "any value" ; multiplied by "1"; results in that exact same value.}.

            →     (1x + 1x² + 2) +  (1x² − 2 − 1x) ;

Rewrite as:

             →     1x + 1x² + 2) +  (1x² − 2 − 1x) ;

Now, let us add the "coefficient" , "1" ; just before the expression:

             "(1x² − 2 − 1x)" ;  

         {since "any value", multiplied by "1" , equals that same value.}.

And rewrite the expression; as follows:

            →     (1x + 1x² + 2) +  1(1x² − 2 − 1x) ;

Now, let us consider the following part of the expression:

                     →  " +1(1x² − 2 − 1x) " ;

________________________________

Note the distributive property of multiplication:

   →  " a(b+c) = ab + ac " ;

and likewise:

   →  " a(b+c+d) = ab + ac + ad " .

________________________________

So; we have:

→  " +1(1x² − 2 − 1x) " ;

  = (+1 * 1x²)  +  (+1 *-2) + (+1*-1x) ;

  =       + 1x²    +    (-2)     +  (-1x) ;

  =       +1x²    −    2   −  1x  ;

  ↔    ( + 1x²  −  1x  −  2)

Now, bring down the "left-hand side of the expression:

1x + 1x² + 2 ;

and add the rest of the expression:

     →  1x  +  1x²  +  2  +   1x²  −  1x  −  2 ;

________________________________

Now, simplify by combining the "like terms" ; as follows:

   +1x² + 1x² = 2x²  ;

   +1x −  1x = 0 ;  

   + 2 −  2  = 0 ;

________________________________

The answer is: " 2x² " .

________________________________

Hope this is helpful to you!

   Best wishes!

________________________________

Answer:

The correct answer is:  " 2x² " .

________________________________

Step-by-step explanation:

________________________________

We are asked:  "What is the sum of:  "x + x² + 2" and "x² − 2 − x" ?

Since we are to find the "sum" ;

 →  We are to "add" these 2 (two) expressions together:

    →     (x + x² + 2) +  (x² − 2 − x) ;

Note:  Let us rewrite the above, by adding the number "1" as a coefficient to:  the values "x" ; and "x² " ;  since there is an "implied coefficient of "1" ;

           → {since:  "any value" ; multiplied by "1"; results in that exact same value.}.

           →     (1x + 1x² + 2) +  (1x² − 2 − 1x) ;

Rewrite as:

            →     1x + 1x² + 2) +  (1x² − 2 − 1x) ;

Now, let us add the "coefficient" , "1" ; just before the expression:

            "(1x² − 2 − 1x)" ;  

        {since "any value", multiplied by "1" , equals that same value.}.

And rewrite the expression; as follows:

           →     (1x + 1x² + 2) +  1(1x² − 2 − 1x) ;

Now, let us consider the following part of the expression:

                    →  " +1(1x² − 2 − 1x) " ;

________________________________

Note the distributive property of multiplication:

  →  " a(b+c) = ab + ac " ;

and likewise:

  →  " a(b+c+d) = ab + ac + ad " .

________________________________

So; we have:

→  " +1(1x² − 2 − 1x) " ;

 = (+1 * 1x²)  +  (+1 *-2) + (+1*-1x) ;

 =       + 1x²    +    (-2)     +  (-1x) ;

 =       +1x²    −    2   −  1x  ;

 ↔    ( + 1x²  −  1x  −  2)

Now, bring down the "left-hand side of the expression:

1x + 1x² + 2 ;

and add the rest of the expression:

    →  1x  +  1x²  +  2  +   1x²  −  1x  −  2 ;

________________________________

Now, simplify by combining the "like terms" ; as follows:

  +1x² + 1x² = 2x²  ;

  +1x −  1x = 0 ;  

  + 2 −  2  = 0 ;

________________________________

The answer is: " 2x² " .

Step-by-step explanation:

Answer:

28

Step-by-step explanation:

number of copies done in 5 minute 15 seconds = 147

60 seconds is equal to 1 minute

1 second is equal to 1/60 minutes

therefore 15 seconds is equal to 1/60 * 15 minutes = 1/4 minutes

thus,

number of copies done in 5 1/4 minute = 147

number of copies done in 1 minute = 147/ 5 1/4   (as 147/21 = 7)

                                                = 147/ (21/4) = 7*4 = 28

Thus, A copy machine makes 28 copies in 1 minute.

Answer:

a. P(X>695)=0.026

b. P(X<485)=0.44

Step-by-step explanation:

The question is incomplete:

a. higher than 695 on the test.

b. at most 485 on the test.

We have a normal distribution with mean 500 and standard deviation of 100 for the test scores. We will use the z-scores to calculate the probabilties with the standard normal distribution table.

a. We want to calculate the probability that a randomly selected student scores higher than 695.

We calculate the z-score and then we calculate the probability:

[tex]z=\dfrac{X-\mu}{\sigma}=\dfrac{695-500}{100}=\dfrac{195}{100}=1.95\\\\\\P(X>695)=P(z>1.95)=0.026[/tex]

a. We want to calculate the probability that a randomly selected student scores at most 485.

We calculate the z-score and then we calculate the probability:

[tex]z=\dfrac{X-\mu}{\sigma}=\dfrac{485-500}{100}=\dfrac{-15}{100}=-0.15\\\\\\P(X<485)=P(z<-0.15)=0.44[/tex]

Answer:

a) Median amount of time that is spent is around 2.3, rounded to 2.

b) 4 unit time

c) Mean amount of time is bigger than the median.

Step-by-step explanation:

Find the given attachment.

Note: Complete Question, along with the diagram is added

Answer:

It would be 27.328  but since it is money, we have to leave the 8 out.

So the answer is 27.32

Step-by-step explanation:

Answer:

$27.33

Step-by-step explanation:

You multiply 12.2 and 2.24 and the answer is 27.328. You then round it to the nearest tenth which is 27.33.

Answer:

A.

Step-by-step explanation:

In the attached file

Answer:  The correct answer is:  

_________________________  

The given "graph" in the bottom right, lowest corner

Step-by-step explanation:

_________________________

Note:  When there is only one (1) equation give for a graph;

          and/or:  only one (1)  "inequality given";  

         we  look for the symbol.

If the symbol is "not" an "equals" symbol (i.e. not an:  =  symbol) ;

 we check for the type of "inequality" symbol.

If there is a:  "less than" (<) ;  or a "greater than" (>) symbol;  the graph of the "inequality" will have "dashed lines" (since there will be a "boundary").

If there is an "inequality" that is a: "less than or equal to" (≤) ;

                                                 or a: "greater than or equal to" (≥) ;

       →   then there will be not be a dashed line when graphed;

          but rather—a "solid line" ;  since "less than or equal to" ;

          or "greater than or equal to" —is similar to:

          "up to AND including"; or: "lesser/fewer than AND including".).

 _________________________  

Note:  We are given the "inequality" :

            →   " y <  x²  + 4x  "  .

_________________________________

Note that we have a "less than" symbol (< ) ; so the graph will have a:

   "solid line" [and not a "dotted line".].

_________________________________

Note that all of the graphs among our 4 answer choices have "dotted lines".

Not that all values (all x and y coordinated) within the "shaded portion" of the corresponding graph are considered part of the graph.  

As such, given any point within the shaded part,  the x and y coordinates must match the inequality (i.e. the given inequality must be true when one puts in the "x-coordinate" and "y-coordinate" into the "given inequality" :

→   " y <  x²  + 4x "  .

_________________________

Likewise, we can take any point within the "white, unshaded" portion of any of the graph, and take the "x-coordinate" and "y-coordinate" of that point, and the inequality: →   " y <  x²  + 4x  "  ;  will not hold true when the "x-coordinate" and "y-coordinate" values of that point— are substituted into the "inequality".  

_________________________

{Note:  Answer is continued on images attached.}.

Wishing you the best!

Answer:

In the figure ∠ABO and ∠BCO have measures equal to 35°.

Step-by-step explanation:

Measure of arc AD = 180-measure of arc CD= 180-125 =55

m<AOB= 55 ( measure of central angle is equal to intercepted arc)

<OAB= 90 degrees (Tangent makes an angle of 90 degrees with the radius)

In triangle AOB ,

< AB0 = 180-(90+55)= 35 degrees( angle sum property of triangle)

In triange BOC ,< BOC=125 ,

m<, BCO=35 degrees

Answer:

∠ABO and ∠BCO

Step-by-step explanation: