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
pav-90 [236]
2 years ago
6

An elementary school class ran 1 mile in an average of 11 minutes with a standard deviation of 3 minutes. Rachel, a student in t

he class, ran 1 mile in 8 minutes. A junior high school class ran 1 mile in an average of 9 minutes, with a standard deviation of 2 minutes. Kenji, a student in the class, ran 1 mile in 8.5 minutes. A high school class ran 1 mile in an average of 7 minutes with a standard deviation of 4 minutes. Nedda, a student in the class, ran 1 mile in 8 minutes. Who is the fastest runner with respect to his or her class?
Mathematics
1 answer:
EleoNora [17]2 years ago
8 0

Answer:

Rachel

Step-by-step explanation:

We need to measure how far (towards the left) are the students from the mean in<em> “standard deviations units”</em>.  

That is to say, if t is the time the student ran the mile and s is the standard deviation of the class, we must find an x such that

mean - x*s = t

For Rachel we have

11 - x*3 = 8, so x = 1.  

Rachel is <em>1 standard deviation far (to the left) from the mean</em> of her class

For Kenji we have

9 - x*2 = 8.5, so x = 0.25

Kenji is <em>0.25 standard deviations far (to the left) from the mean</em> of his class

For Nedda we have

7 - x*4 = 8, so x = 0.25

Nedda is also 0.25 standard deviations far (to the left) from the mean of his class.

As Rachel is the farthest from the mean of her class in term of standard deviations, Rachel is the fastest runner with respect to her class.

You might be interested in
What is the value of this equation 38&gt;-5x+3&gt;18
Bond [772]
Its called inequality 
8 0
3 years ago
If 8y-8=24 find the value of 2y
Aloiza [94]

Answer:

8

Step-by-step explanation:

8y-8=24

+8 +8

8y=32

32/8 = 4

y=4

4*2=8

4 0
2 years ago
Read 2 more answers
Raymond has taken a position as the navigator on a speed boat racing team. The team entered a race that starts at Daytona Beach,
erik [133]
Using the rules of cosines, the <span>measure of the turn between the second and third legs of the race</span> is given by

\cos^{-1}\left( \frac{180^2+160^2-140^2}{2\times180\times160} \right)=\cos^{-1}\left( \frac{32,400+26,600-19,600}{57,600} \right) \\  \\ =\cos^{-1}\left( \frac{39,400}{57,600} \right)=\cos^{-1}(0.6840)\approx47^o
4 0
3 years ago
Read 2 more answers
I don’t really understand?
aksik [14]

Go over the x axis up 5  and over the y axis left 1

3 0
3 years ago
has vertices J(3, –1), K(4, –4), and L(1, –3). Determine if is an equilateral, isosceles, or scalene triangle. A. equilateral B.
Juli2301 [7.4K]
Answer c) scalene :-) ....
7 0
3 years ago
Read 2 more answers
Other questions:
  • 4x^2-4x=+1 by factoring ​
    5·1 answer
  • [MA5T10 Dj Name the property being illustrated.
    12·1 answer
  • $500 invested at 8% compounded quarterly after a period of 2 1/2 years
    10·2 answers
  • Help Please im struggling dont have to answer just please explain what I have to do
    6·2 answers
  • Help plz<br> will mark brainliest
    7·1 answer
  • Deja had two baskets of berries. One of the baskets has 3 3/8 pounds of berries and the other basket has 2 7/8 pounds of berries
    5·1 answer
  • Tamia’s mother is 3 times older than Tamia. The sum of their age is 52. How old is Tamia and her mom?
    5·1 answer
  • Assume that an image is created by rotating another figure 180 degrees. Explain how you can you could determine the location of
    10·1 answer
  • Can someone pls help me <br> Ill give Brainly<br> NO BOTS OR ILL REPORT YOU
    15·1 answer
  • A sub sandwich shop offers 22 toppings to choose from. How many ways could a person choose a 4-topping sandwich?
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!