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
Sav [38]
3 years ago
15

The mean number of points in 1977 was 1189 points with standard deviation of 397 points. With a roughly normal distribution, wha

t percent of performances would fall between 395 and 1983 points?
Your answer
A. 100%
B. 68%
C. 95%
D.99.7%
Mathematics
1 answer:
KonstantinChe [14]3 years ago
5 0

Answer:

C. 95%

Step-by-step explanation:

The Empirical Rule states that, for a normally distributed random variable:

Approximately 68% of the measures are within 1 standard deviation of the mean.

Approximately 95% of the measures are within 2 standard deviations of the mean.

Approximately 99.7% of the measures are within 3 standard deviations of the mean.

In this problem, we have that:

Mean of 1189 points, standard deviation of 397 points.

Percentage between 395 and 1983 points?

395 = 1189 - 2*397

1983 = 1189 + 2*397

So within 2 standard deviations of the mean, which by the Empirical Rule is approximately 95%, and the answer is option C.

You might be interested in
Factor: Show all work<br> x^2-6x+9
yKpoI14uk [10]
HI THIS IS VERY HARD CAN U GIVE ME MORE TIME
4 0
4 years ago
The sides of a triangle are 1, x, and x2. what are possible values of x?
Whitepunk [10]
The sides of the triangle are given as 1, x, and x².

The principle of triangle inequality requires that the sum of the lengths of any two sides should be equal to, or greater than the third side.

Consider 3 cases
Case (a):  x < 1,
      Then in decreasing size, the lengths are 1, x, and x².
      We require that x² + x ≥ 1
      Solve x² + x - 1 = 
      x = 0.5[-1 +/- √(1+4)] = 0.618 or -1.618.
      Reject the negative length.
     Therefore, the lengths are 0.382, 0.618 and 1.

Case (b): x = 1
   This creates an equilateral triangle with equal sides
    The sides are 1, 1 and 1.

Case (c): x>1
  In increasing order, the lengths are 1, x, and x².
  We require that x + 1 ≥ x²
  Solve x² - x - 1 = 0
  x = 0.5[1 +/- √(1+4)] = 1.6118 or -0.618
  Reject the negative answr.
 The lengths are 1, 1.618 and 2.618.

Answer:
The possible lengths of the sides are
(a) 0.382, 0.618 and 1
(b) 1, 1 and 1.
(c) 2.618, 1.618 and 1.

7 0
3 years ago
The average price of a movie ticket in the United States from 1980 to 2000 can be modeled by the expression, 2.75+0.10x, where x
MissTica

Answer:

<h2>$4.7</h2>

Step-by-step explanation:

step one:

Let the cost be y

to solve for the cost of  a movie ticket, we need to solve the expression

y=2.75+0.10x

step two:

given that x is the number of years between 1980-2000

the number of years is 20years

put x= 20 in the expression for the cost we have

y=2.75+0.10(20)

y=2.7+2

y=$4.7

5 0
3 years ago
Find the measure of the angle to the nearest tenth of a degree.
Digiron [165]

Answer:

Option B is correct.

Step-by-step explanation:

We need to find the value of S in cos S = 0.9092

cos S = 0.9092

To find value of S we will find cos^-1(0.9092) i.e

S = cos^-1 (0.9092)

S = 24.6 °

So, the measure of the angle to the nearest tenth of a degree of cos S = 0.9092 is 24.6°

So, Option B is correct.

8 0
3 years ago
A number cube is rolled 14 times and the results are recorded in the table.
marshall27 [118]

Answer:

D.5/14

Because 4 appeared five times over the total

8 0
2 years ago
Other questions:
  • A trail is 13.5 miles Lilongwe. There are markers every 0.25 miles. How many markers are there
    8·1 answer
  • How do you factor out the Greatest Common Factor of polynomials?
    15·1 answer
  • Let \[f(x) = \frac{3x - 7}{x + 1}.\] find the domain of f. give your answer as an interval.
    13·1 answer
  • Is there any one who can do most of these questions pls and thank you
    12·1 answer
  • A lot cost $120,000 the house cost 3 times more than a lot how much did the house cost
    14·1 answer
  • Alex purchased a new car for 28,000. The cars value depreciates 7.25% each year. What will be value of the car 5 years after it
    5·2 answers
  • Solve the system of linear equations by substitution.<br><br> y−x=0<br> 2x−5y=9
    5·1 answer
  • An ice sculpture measures 65 inches and melts continuously by 3% per minute. Find the height of a sculpture after 15 minutes. Ro
    12·1 answer
  • If f(x) = V7x + 31 , find f(0).
    9·1 answer
  • Can you help me with this pls
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!