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
S_A_V [24]
3 years ago
8

In a statistics​ class, the standard deviation of the heights of all students was 3.8 inches. The standard deviation of the heig

hts of males was 3.3 inches and the standard deviation of females was 3.1 inches. Why is the standard deviation of the entire class more than the standard deviation of the males and females considered​ separately?
Mathematics
1 answer:
goblinko [34]3 years ago
4 0

Answer:

The reason why standard deviation of the entire class is greater than standard deviation of males and females considered separately, is that mean values for males and females are different from each other.

Step-by-step explanation:

The concept of mean is well represented by the following formula

mean = \frac{(x1 + x2 + x3 + ..... + xn)}{N}, where x1, x2, xn are the observations and N is the number of observations (population).

Standard deviation represents the distance between each observation and the mean of the population (all observations). The formula for this parameter is:

Standard deviation =√[((x1 - x)² + (x2-x)² + ....+ (xn-x)²)/N-1], where x1, x2,..., xn are the observations and x is the mean value.

In this case you have that each height registered is an observation and the number of observations represents the N value. As you can see if the mean for males is different from that of females their standard deviation will be different too. Usually males have heigths greater than that of females (1.77 vs 1.64, in USA for example), and heights inside each group will be more similar than between groups. Then, when you mix all observation there will be an increase in standard deviation, because you are mixing very different heigths

You might be interested in
Will mark brainless for first response!!!
ivann1987 [24]
1. (2x + 1)(x - 7)
2. -x - 4
3. -31x -35
4. 57x + 112
5. (-x) (-x)
5 0
2 years ago
On a timed session please help I have one more question after this.....
olya-2409 [2.1K]

The coffee shop used 52 pounds of Type A coffee.

Step-by-step explanation:

Cost of Type A coffee per pound = 5.25

Cost of Type B coffee per pound = 4.10

Total pounds used in blend = 142

Total cost = 642.00

Let,

x be the pounds of Type A coffee used

y be the pounds of Type B coffee used

According to given statement;

x+y=142      Eqn 1

5.25x+4.10y=642.00   Eqn 2

Multiplying Eqn 1 by 4.10

4.10(x+y=142)\\4.10x+4.10y=582.20\ \ \ Eqn\ 3

Subtracting Eqn 3 from Eqn 2

(5.25x+4.10y)-(4.10x+4.10y)=642.00-582.20\\5.25x+4.10y-4.10x-4.10y=59.80\\1.15x=59.80\\

Dividing both sides by 1.15

\frac{1.15x}{1.15}=\frac{59.80}{1.15}\\x=52\\

The coffee shop used 52 pounds of Type A coffee.

Keywords: linear equation, elimination method

Learn more about elimination method at:

  • brainly.com/question/10677255
  • brainly.com/question/10689103

#LearnwithBrainly

5 0
3 years ago
Type the correct answer in each box. Use numerals instead of words.
Leokris [45]

Answer:

P=4/250=0.016

nearest tenth=0.02

1.6%

4 0
2 years ago
celia donates 10.2 inches of her hair to a company that makes wings.danielle donates 2.4 fewer inches of her hair than celia.how
Mashcka [7]

mathematically the answer to that is 18 because 10.2 minus 2.4 is equal to the difference of 7.8 and 7.8 plus 10.2 is equal to the sum of exactly and positively 18

7 0
3 years ago
Find the additive inverse. <br> 6
Irina18 [472]
-6 it is just the opposite of the number. So a positive would be a negative and a negative a positive. So the answer to your question is -6. 
6 0
3 years ago
Other questions:
  • 30 - 30 •5x2 +8.<br> Please help
    8·1 answer
  • Jolie has just purchased a new purse in the shape of a rectangular prism to match her favorite shoes. The purse has a length of
    12·1 answer
  • Dana buys dress shirts from a clothing manufacturer for s dollars each, and then sells the dress shirts in her retail clothing s
    13·1 answer
  • Instructions: Find the measure of the indicated angle to the<br> nearest degree
    9·1 answer
  • D+7/−3=4 Please help me
    6·2 answers
  • Write an explicit equation for the arithmetic sequence<br> 3,7,11,15,19
    5·1 answer
  • Find the volume of the square pyramid with base area 49in^2 and a height of 8 inches. Round your answer to two decimal places
    9·1 answer
  • Explain the reasoning to your answer. Will mark you the Brainliest
    6·2 answers
  • Task;2round off the following numbers to the highest place value.
    10·1 answer
  • Help with these questions pls​
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!