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
Anit [1.1K]
3 years ago
10

The College Board originally scaled SAT scores so that the scores for each section were approximately normally distributed with

a mean of 500 and a standard deviation of 100. Assuming scores follow a bell-shaped distribution, use the empirical rule to find the percentage of students who scored less than 400. a. 84% b. 16%
Mathematics
1 answer:
kirza4 [7]3 years ago
6 0

Answer:

b. 16%

Step-by-step explanation:

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

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

95% of the measures are within 2 standard deviation of the mean.

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

In this problem, we have that:

Mean = 500

Standard deviation = 100

Percentage of students who scored less than 400:

400 = 500 - 1*100

So 400 is one standard deviation below the mean.

The normal distribution is symmetric, which means that 50% of the measures are below the mean and 50% are above.

Of those who are below, 68% are within 1 standard deviation of the mean, that is, between 400 and 500. So 100-68 = 32% are below 400.

0.5*0.32 = 0.16 = 16%

So the correct answer is:

b. 16%

You might be interested in
Line segment ST has endpoints (3,2) and (7,4). What is the equation for the perpendicular bisecotr?
Lena [83]
We need Vector ST which is just T - S

(7-3.4-2) = (4,2)

So now we need the perpindicular. The easiest way to do this, is to know that , in R2 that the perindicular is just the negatice inverse.  So its (2,-4)
7 0
3 years ago
What is the opposite reciprocal of 6
german
Let's find the reciprocal.
6/1 is the fraction of 6. Flipped is 1/6.
The reciprocal is 1/6.
The opposite means either positive or negative. Since it's already positive, it'll turn negative.
-1/6.
8 0
3 years ago
I NEED HELP! ASAP, THIS IS SO HARD AND MY BRAIN HURTS, IF U HELP ME WITH OTHER QUESTIONS LIKE THIS ILL GIVE U 50+ POINTS
Dimas [21]

Answer:

24.3

Step-by-step explanation:

We need to follow the order of operations PEMDAS:

  • Parentheses
  • Exponents
  • Multiplication and Division (from left to right)
  • Addition and Subtraction (from left to right)

Carry out the operation in the parentheses first:

   3³ + 14.7 ÷ 7 - (1.2 × 4)

⇒ 3³ + 14.7 ÷ 7 - 4.8

Now the exponent:

⇒ 3³ + 14.7 ÷ 7 - 4.8

⇒ (3 × 3 × 3) + 14.7 ÷ 7 - 4.8

⇒ 27 + 14.7 ÷ 7 - 4.8

Now, the division (there is no multiplication):

⇒ 27 + 14.7 ÷ 7 - 4.8

⇒ 27 + 2.1 - 4.8

Finally, carry out the addition and subtraction (from left to right)

⇒ 27 + 2.1 - 4.8

⇒ 29.1 - 4.8

⇒ 24.3

8 0
2 years ago
What is 5 and 39/50 as a improper fraction
schepotkina [342]

Answer:

(195)/50

Step-by-step explanation:

so you do (5*39)/50

(195)/50

7 0
3 years ago
Before starting his job, Clayton had been on an airplane 3 times. Since then, he has flown 6 times each year.
xz_007 [3.2K]

Answer:

f = 6y + 3

Step-by-step explanation:

<u>The equation to reflect this condition is:</u>

  • f = 6y + 3

<u>Where</u>

  • 3 - is constant, the initial number of flights
  • 6 - coefficient, number of flights per year
  • y- number of years
  • f- total number of flights
8 0
3 years ago
Other questions:
  • Trig please help
    10·2 answers
  • M is the midpoint of . The coordinates of A are (2,3) and the coordinates of M are (4.5,6). Find the coordinates of B.
    5·1 answer
  • C. What patterns do you notice in the list of fractions 1/5, 1/25, 1/125, 1/625, 1/3125 ?
    15·1 answer
  • The oil tank in the shape of a cylinder has a diameter of 40 feet and a height of 32 feet. Which expression can be used to find
    11·2 answers
  • ===============================================================
    10·1 answer
  • Find the dimension of a rectangle whose width is 9 miles less than its length and whose area is 90 square miles
    13·1 answer
  • Please help me out i need it with these questions!!!!
    10·1 answer
  • Express x^2 +12+11 in the form (x+p)^2 +q
    8·1 answer
  • Can someone please help?
    11·1 answer
  • 10. What is the value of ? A. 47.5° B, 85° 95° C. 95° С D. 132.59​
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!