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
Crazy boy [7]
2 years ago
6

Scores on the SAT are approximately normally distributed. One year, the average score on the Math SAT was 500 and the standard d

eviation was 120. What was the score of a person who did better than 85% of all the test-takers
Mathematics
1 answer:
Nookie1986 [14]2 years ago
8 0

Answer:

The score of a person who did better than 85% of all the test-takers was of 624.44.

Step-by-step explanation:

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean \mu and standard deviation \sigma, the z-score of a measure X is given by:

Z = \frac{X - \mu}{\sigma}

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

One year, the average score on the Math SAT was 500 and the standard deviation was 120.

This means that \mu = 500, \sigma = 120

What was the score of a person who did better than 85% of all the test-takers?

The 85th percentile, which is X when Z has a p-value of 0.85, so X when Z = 1.037.

Z = \frac{X - \mu}{\sigma}

1.037 = \frac{X - 500}{120}

X - 500 = 1.037*120

X = 624.44

The score of a person who did better than 85% of all the test-takers was of 624.44.

You might be interested in
What is 5 1/2% simplified as a fraction in simplistic form
zzz [600]

Answer:

11/200

Step-by-step explanation:

=5.5%

=5.5/100

=55/1000

=55/5

------------

1000/5

= 11/200

8 0
2 years ago
Sue either travels by bus or walks when she visits the shops. The probability that she catches the bus from the shops is 0.7. Sh
Alina [70]

Corrected Question

Sue travels by bus or walks when she visits the shops. The probability that she catches the bus to the shops is 0.4. The probability she catches the bus from the shops is 0.7. Show the probability that Sue walks at one way is 0.72

Answer:

P(A \cup B) =0.72 (Proved)

Step-by-step explanation:

Sue travels by bus or walks when she visits the shops.

Let the event that she catches the bus to the shop=A

Let the event that she catches the bus from the shop=B

P(A)=0.4

P(B)=0.7

Both A and B are independent events.

Therefore,Probability that she catches the bus to and from the shop:

P(A∩B) = 0.4 X 0.7= 0.28

Probability Sue walks at least one way P(A \cup B) = 1 - P(A \cap B)

= 1 - 0.28\\= 0.72

Hence, the probability that Sue walks at least one way is 0.72.

8 0
2 years ago
A car bought for $13,000 depreciates at 15% per year. Use an exponential function to find the value of the car after 5 years.
earnstyle [38]

Answer:

$5768.1

Step-by-step explanation:

Given data

Cost price= $13,000

Depreciation= 15%

Time= 5 years

The expression for the depreciation is given below

A= P(1-r)^t

Substitute

A=13000(1-0.15)^5

A=13000(0.85)^5

A=13000*0.4437

A=$5768.1

Hence after 5 years, the car will be $5768.1

7 0
2 years ago
la pyramide du Louvre cest une pyramide a base carrée de 35,4m de large et de 21,6m de haut calculer l'inclinaison dune face par
MrRissso [65]

Answer:

c'est une pyramide régulière à base carrée de35.4 m de large et de 21.6 m de haut. calculer l'inclinaison d'une face par rapport à l'horizontale. ... dans le triangle rectangle SHA: tg SAH = 21,6/17,7 donc l'angle SAH = 50,66° ...

Step-by-step explanation:

7 0
3 years ago
A box of blueberries is 2/5 full. Janet and her friends had each eaten 1/10 of a box of blueberries. How many people are blueber
anyanavicka [17]

In this problem, we have to find the factor which will make (1 / 10) equal to (2 / 5). Therefore we can write it as:

x (1 / 10) = 2 / 5

where x is the number of people who ate the blueberries

x = (2 / 5) / (1 / 10)

x = 4

 

<span>Therefore 4 people ate the blueberries.</span>

7 0
3 years ago
Read 2 more answers
Other questions:
  • Consider the relationship between the number of bids an item on eBay received and the item's selling price. The following is a s
    6·1 answer
  • Whats the answer to this problem
    11·1 answer
  • fresh water from lakes accounts for only 0.001 of the world's water supply. write this decimal as a percent
    15·2 answers
  • Plzz help will give branlisest
    15·2 answers
  • Kerry has 77 dolls. Perry has e more dolls than Kerry. Write the expression that shows how
    14·1 answer
  • here is the pic :))))))))))))))))))))))))))))))))))))))))))))))))))) sorry for doing so many smiles it would not let me post thi
    8·2 answers
  • Solve for x: 3/4 x + 5/8 = 4x
    11·1 answer
  • Compare and contrast 2d and 3d shapes
    8·2 answers
  • Riddle: What is seen in the middle of March and April that can’t be seen at the beginning or end of either month?
    5·2 answers
  • A number that is being divided by another number is called the
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!