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
UkoKoshka [18]
3 years ago
8

Evelyn earned a score of 86 on Exam A that had a mean of 71 and a standard deviation of 20. She is about to take Exam B that has

a mean of 550 and a standard deviation of 40. How well must Evelyn score on Exam B in order to do equivalently well as she did on Exam A? Assume that scores on each exam are normally distributed.
Mathematics
1 answer:
Leno4ka [110]3 years ago
4 0

Answer:

580

Step-by-step explanation:

Assuming that the answer should be in terms of z scores, we can calculate the z score as

z = (observed value - mean)/(standard deviation)

For the first exam, the observed value is 86, the mean is 71, and the standard deviation is 20. The z score fot that exam is

z = (86-71)/20 = 0.75

Then, for the second exam, Evelyn has to do equivalently well, so the z score must be the same. Therefore, we have

0.75 = (observed score - 550)/40

multiply both sides by 40 to remove a denominator

0.75 * 40 = observed score - 550

add 550 to both sides to isolate the observed score

0.75 * 40 + 550 = observed score = 580

You might be interested in
Solve for m. <br> 2(5m + 4) = 2 (3m - 10)
agasfer [191]
2(5m+4)=2(3m-10)
10m+8= 6m-20
-6m         -6m
4m+8= -20
      -8     -8
4m= -28
m = -7
3 0
3 years ago
What is the product of -3 and 5?
mina [271]

Answer:

2

Step-by-step explanation:

6 0
3 years ago
Read 2 more answers
Yesterday, I ran less than 5 kilometers but more than. 1,200 meters. How far could I have run?
taurus [48]
Less then 5 kilometers and more then 1,200 meters obv
7 0
2 years ago
A family wants to build a rectangular garden on one side of a barn. If 600 feet of fencing is available to use, then what is the
vovangra [49]

Answer: (A) A=300l-l^{2}

               (B) Length varies between 1 and 150

               (C) Largest area is 22500ft²

Step-by-step explanation: Suppose length is l and width is w.

The rectangular garden has perimeter of 600ft, which is mathematically represented as

2l+2w=600

Area of a rectangle is calculated as

A=lw

Now, we have a system of equations:

2l+2w=600

A=lw

Isolate w, so we have l:

2w=600-2l

w = 300 - l

Substitute in the area equation:

A = l(300 - l)

A = 300l - l²

(A) <u>Function of area in terms of length is given by </u><u>A = 300l - l²</u>

(B) The practical domain for this function is values between 1 and 150.

(C) For the largest area, we need to determine the largest garden possible. For that, we take first derivative of the function:

A' = 300 - 2l

Find the values of l when A'=0:

300 - 2l = 0

2l = 300

l = 150

Replace l in the equation:

w = 300 - 150

w = 150

Now, calculate the largest area:

A = 150*150

A = 22500

<u>The largest area the fence can enclose is </u><u>22500ft².</u>

4 0
3 years ago
Sep 08, 2:59:48 PM
Anuta_ua [19.1K]

Answer:

5c + 1.3d - 6.3

Step-by-step explanation:

5c-(-1.3d-6.3)\\\\\boxed{5c+1.3d-6.3}\\\\\left \{ {{-1*-1.3d=1.3d} \atop {-1*6.3=-6.3}} \right.

Hope this helps.

8 0
3 years ago
Other questions:
  • PLEASE HELP!! Find the sixth term of the sequence 14,9,4,..
    13·1 answer
  • What are the solutions to this quadratic equation? x^2+13=8x+3
    15·2 answers
  • One plane at 520 feet is ascending at a rate of 40 feet per minute. While another plane at 3800 feet is descending at a rate of
    11·1 answer
  • The price of a holiday was decreased by 12% to £600. What was the price before the decrease? Give your answer to the nearest pen
    15·2 answers
  • The average income, I, in dollars, of a lawyer with an age of x years is modeled with the following function: I = -425x^2 + 45,5
    10·1 answer
  • This is related to my grade
    8·1 answer
  • PLEASE HELP I DONT KNOW HOW TO DO IT PLEASEEEE
    6·2 answers
  • 1 A camera is capable of snapping 3/4 of a picture per second. How many pictures can be snapped within a 36-second period?
    7·1 answer
  • Y+16= -8<br> Another Question heheh
    7·2 answers
  • Christine is working on learning new recipes because she wants to be prepared when she leaves for college. after her first week,
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!