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
DIA [1.3K]
3 years ago
9

Scores on a test are normally distributed with a mean of 68.2 and a standard deviation of 10.4. Estimate the probability that am

ong 75 randomly selscted students, at least 20 of them score greater that 78.
Mathematics
1 answer:
tekilochka [14]3 years ago
7 0
First, find the probability of scoring higher than 78. Scores are normally distributed, so you have

\mathbb P(X>78)=\mathbb P\left(\dfrac{X-68.2}{10.4}>\dfrac{78-68.2}{10.4}\right)\approx\mathbb P(Z>0.9423)\approx0.173

Now, the event that any given student scores higher than 78 follows a binomial distribution. Here you have 75 total students (so n=75) with success probability p=0.173.

So the probability of getting 20 students that fit the criterion is

\mathbb P(Y=20)=\dbinom{75}{20}p^{20}(1-p)^{75-20}\approx0.0134
You might be interested in
Please find the volume
Sindrei [870]

Answer:

27/4 units^3

Step-by-step explanation:

V= area of the base × length

V= 3 3/8 × 2

= 27/4 units^3

4 0
3 years ago
Read 2 more answers
A car travels at a speed of 55 kilometers per hour.Find the distance travelled by the car in 12 minutes and 30 seconds.Find the
never [62]

Answer:

Step-by-step explanation:

(distance) d = (speed) s * t (time)

                    = 55km/h * 12.30m/s

                    = 11.275 km

                    = 11.275 * 1000

                    = 11275m

4 0
3 years ago
Please help! Will give brainliest!
Zanzabum

Answer:

Step-by-step explanation:

6 0
3 years ago
Tom,Scott and dawn sold cookies at the school fair.
aleksklad [387]
First of all work out how many tom and scott sold.
tom sold 60% of 90 cookies which is 54.
scott sold 2/3 of 150 cookies which is 100.
altogether the three of them sold 54+100+46 cookies which is 200.
Dawn sold 46 of these 200 cookies. To work out the percentage we have both the numbers to get 23 out of 100. We halved those numbers because a percentage is out of 100 we halved it to get it out of 100.
so 23 out of 100 is 23% so dawn sold 23%of the cookies.

Hope this helps :)
3 0
3 years ago
(m) रेखीय फलन (Linear function)
Law Incorporation [45]

Answer:

???????????????????????????????

Step-by-step explanation:

5 0
3 years ago
Other questions:
  • The difference between two integers is at most 16. the smaller integer is 12. what is the larger integer
    6·1 answer
  • the current temperature in smalltown is 20 degrees fahrenheit. this is 6 degrees less than twice the temperature that it was six
    6·1 answer
  • You may remember that the area of a triangle is A=12B⋅H, where B is the base of the triangle and H is the height. Suppose that t
    15·1 answer
  • Is the expression X^3 equivalent to X^3•3•3
    7·1 answer
  • 45 620 000 to the nearest million​
    11·2 answers
  • The angle of elevation from the base to the top of a waterslide is 13 degrees. The slide extends horizontally 58.2 meters. Appro
    10·1 answer
  • Maryam has 12 cookies. She wants to give each of her 4 friends the same number of cookies. How many cookies will Maryam give eac
    12·2 answers
  • What are the potential solutions of
    15·1 answer
  • PLZ HELP I NEED THIS TODAY! Choices are:
    7·2 answers
  • Please help me with this! I’m so lost :((
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!