1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
weeeeeb [17]
3 years ago
12

Suppose on a certain test, fifty students earn a perfect score and fifty students earn a zero. determine the mean grade and stan

dard deviation among the one hundred students.
a. mean grade among the one hundred students is a0
b. standard deviation:
Mathematics
2 answers:
kodGreya [7K]3 years ago
5 0

Answer:

Mean=50.

standard deviation=50.

Step-by-step explanation:

Let the perfect score be 100.

The mean(average) of a data is given by: Mean=\frac{sum of data points}{number of data points}

Here the number of data points are 100. out of which 50 attains a value 100,and 50 attains value 0.

so, sum of data points=50×100+50×0=5000.

Mean=\frac{5000}{100}

Mean=50.

"Now the standard deviation of data points are calculated by firstly subtracting mean from every entry and then square the number and take it as new entry and calculate the mean of the new data entry and lastly taking the square root of this new mean".

Here if 50 is subtracted from each entry the new entry will have 50 entries as '50' and 50 entries as '-50'.

next on squaring we will have all the 100 entries as '2500'.

now the mean of these entries is: \frac{2500\times100}{100}

                                                         =2500

taking it's squareroot we have \sqrt{2500}=50

Hence, standard deviation=50.




yKpoI14uk [10]3 years ago
5 0

Answer:

mean is 50

standard deviation is 50

Step-by-step explanation:

as for finding the mean, if half get 100 and half get nothing, all you do is divide 100 by 2. that gets you 50.

as for standard deviation:

first you want to subtract the mean (fifty) from all your numbers.

100-50=50\\0-50=-50 (remember we still have fifty of each)

now square those numbers you have

50^{2} = 2500\\(-50)^{2}=2500

now's the time to remember you have fifty of each value. go ahead and multiply fify into each.

50*2500=125,000\\50*2500=125,000

now add em up

125,000+125,000= 250000

divide by 100

250000/100= 2500

now get the square root of that

\sqrt{2500}=50

and boom, you have your standard deviation.

hope this helped

You might be interested in
What is the square root of 1675
liubo4ka [24]
40.9267 is the square root
7 0
2 years ago
Read 2 more answers
Find the perimeter and area of the figure. Round to the nearest tenth if necessary. 33.7 mm; 108 mm2 33.7 mm; 54 mm2 30.7 mm; 50
Deffense [45]

Answer:

Perimeter: 33.7 mm

Area: 54 mm

Step-by-step explanation:

If you do 12 + 9.7 + 12 you will get the perimeter, and to get the area you would use the formula A = \frac{1}{2} x base x height. Since the base is 12 and the height is 9, you would do 12 x 9 x 0.5 to get 54 mm for the area of the triangle.

8 0
2 years ago
Find the value of x in a triangle. x-20, x+10, x-20
tatyana61 [14]

The value of the angles should be. (x-40°). , (x-20°), (½x-10°) , not (x-40°) + (x-20°)+(½x-10°)

Sum of all the interior angles of a triangle is 180°.

So a equation can be made by the given data,

(x-40°) + (x-20°) + (½ x-10°) = 180°

x-40°+x-20°+½x-10° = 180°

2x+½x -60°-10° = 180°

5/2 x - 70° = 180°

5/2 x = 180° + 70°

5/2 x = 250°

x = 250° × 2/5

x = 50° × 2

x = 100°

So the angles are

x-40° = 100°-40° = 60°

x-20° = 100°–20° = 80°

½x-10° = ½(100)° - 10° = 50° -10° = 40°

The answer can be checked by putting the values of the angle we got in the second statement i.e. Sum of all the interior angles of a triangle is 180°.

60° + 80° + 40° = 100° + 80° = 180°

6 0
3 years ago
Please help i don’t understand
34kurt

Answer:

D

Step-by-step explanation:

First of, let's make a table for y = cos(x)

(x , y): (0 , 1) (π/2 , 0) (π , -1) (3π/2 , 0) (2π , 1)

Now, making a table for y = 2cos(x) is simple. We just have to multiply all the y-values from the previous table by 2.

(x , y): (0 , 2) (π/2 , 0) (π , -2) (3π/2 , 0) (2π , 2)

Graphing these coordinates, we find that the answer is D.

4 0
2 years ago
What is the midpoint of AB?
Lana71 [14]

Answer:

the answer is 0

Step-by-step explanation:

just count from -6 all the way to 8 then you will find out that the there are 15 numbers from point a to point b then count from both sides the center

6 0
2 years ago
Other questions:
  • An archaeologist descends 22 feet into a canyon then climbs up 15 feet what is his final position
    7·1 answer
  • 1. Write a number whose square is between 200 and 300.
    9·1 answer
  • I need help -6x<-18 or x+45-1
    9·1 answer
  • Harry was given an assignment. He had 42 days to get 336 tasks done at work.
    12·1 answer
  • Multiplying Polynomials: Tutorial
    5·1 answer
  • Which of the following is a pair of equivalent radical expressions?
    12·1 answer
  • Use associative property of multiplication to write an expression equivalent to (18*7)*y
    14·1 answer
  • Write and solve an equation for the scenario below: Jake made $24 this week. This was 3 less than three times the amount he made
    14·1 answer
  • Please answer I am struggling
    9·1 answer
  • TIME SENSITIVE!!! What will the first row of this multiplication be? (first image is the problem, second is the options)
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!