Need help asap!!! 48 points

An English professor assigns letter grades on a test according to the following scheme. A: Top 5% of scores B: Scores below the

tangare [24]

Answer:

Grade D score:

$69 \leq x \leq 74$

Step-by-step explanation:

We are given the following information in the question:

Mean, μ = 78.8

Standard Deviation, σ = 7.1

We are given that the distribution of scores on test is a bell shaped distribution that is a normal distribution.

Formula:

$z_{score} = \displaystyle\frac{x-\mu}{\sigma}$

D: Scores below the top 77% and above the bottom 9%

We have to find the value of x such that the probability is 0.77

$P( X > x) = P( z > \displaystyle\frac{x - 78.8}{7.1})=0.77$

$= 1 -P( z \leq \displaystyle\frac{x - 78.8}{7.1})=0.77$

$=P( z \leq \displaystyle\frac{x - 78.8}{7.1})=0.23$

Calculation the value from standard normal z table, we have,

$\displaystyle\frac{x - 78.8}{7.1} =-0.739\\\\x = 73.55$

We have to find the value of x such that the probability is 0.09

$P(X < 0.09) = \\\\P( X < x) = P( z < \displaystyle\frac{x - 78.8}{7.1})=0.09$

Calculation the value from standard normal z table, we have,

$\displaystyle\frac{x - 78.8}{7.1} = -1.341\\\\x = 69.27$

Thus, the numerical value of score to achieve grade D is

$69 \leq x \leq 74$

6 0

3 years ago

There are 8 red, 4 green and 12 yellow balls in a box. If you choose one ball from the box, what is the probability that it will

rusak2 [61]

Answer:

50% percent chance the ball will be yellow

Step-by-step explanation:

Find the amount of all the balls-24 and the amount of yellow balls-12

Then divide the number of yellow balls by the number of total balls.

12÷24=0.5

0.5=50%

8 0

3 years ago

What is -3/5 as a decimal?????

Leona [35]

Answer:

-0.6

Step-by-step explanation:

6 0

3 years ago

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A basketball coach keeps track of the points scored per game for all of the players . She gives a trophy to the player with the

Verdich [7]

Your Question was incomplete so I will solve a similar question that will help you to tackle this kind of questions.

Q)Two university female basketball players are being considered for an award to be given to the most consistent player with the highest scoring average for the season. The number of points scored per game for all games played during the season is given by the following table. ( Table Attached)

a) Calculate the population mean and population standard deviation of the number of points scored per game for each player.

(b) Using the results of part (a) which player should receive the award.

Answer:

<h3>Player B should receive the award.</h3><h3>Step-by-step explanation:</h3>

Points of player A:- 5,32,45,25,8,10,35,12,37,21

First we will calculate the mean for player A

∑x = 5 + 32 + 45 + 25 + 8 + 10 + 35 + 12 + 37 + 21

∑x = 230

N = 10

Mean = µ= ∑x/N = 230/10 = 23

Now we will calculate the standard deviation for Player A

x - µ = -18 , 9, 22, 2, -15, -13, 12, 11, 14, -2

(x - µ)^2 = 324, 81, 484, 4, 225, 169, 144, 121, 196, 4

∑(x - µ)^2 = 1752

σ = sqrt( ∑((x - µ)^2/N) )

σ = sqrt(1752/10)

σ = 13.236

Calculating mean for player B:

Points of player B = 18, 20, 22, 15, 35, 24, 29, 19, 25, 23

∑x = 18 + 20 + 22 + 15 + 35 + 24 + 29 + 19 + 25 + 23

N =10

µ = 230/10

µ = 23

Calculating standard deviation for player B:

(x - µ ) = -5, -3, -1, -8, 12, 1, 6, -4, 2, 0

(x -µ )^2 = 25, 9, 1, 64, 144, 1, 36, 16, 4, 0

∑(x - µ)^2 = 300

σ = sqrt(300/10)

σ = 5.48

Since both Player A and Player B have same mean we will calculated the coefficient of variation for both the players.

For player A:

σa/µa *100 = 13.24/23 *100 = 57.56

For Player B:

σb/µb *100 = 5.48/23 * 100 = 23.82

Since the coefficient of variation of Player B is less than Player A hence Player B should receive the award.

3 0

3 years ago

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|-5x-5|=45 what is the solutions

Paha777 [63]

Answer:-10

Step-by-step explanation:

45 +5=-5x

-5x=50

X=-10

7 0

3 years ago

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