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
8090 [49]
3 years ago
6

In a class of 100 students, 25 students have hardcover and 75 students have paperback textbooks for the course. If you randomly

choose 10 students in this class, fnd the probability that 2 of them have hardcover texts in the following ways: a. the exact probability b. approximate probability using a binomial distribution
Mathematics
1 answer:
galina1969 [7]3 years ago
6 0

h = prob of hardcover = .25

p = prob of paperback = .75

a.

Prob(2 hardcover of 10) = (10 choose 2) (.25)^2 (.75)^8

= ( 10(9)/2 ) (1/4^10) (1^2 3^8)

= 295245/1048576

≈ 28.15%

b.

I think I just did the binomial distribution.  We can approximate it as a normal distribution. The mean and variance in this case are computed thus:

N=10, n=2

μ = Np = 2.5

σ² = Npq = 1.875

σ = 1.3693

P(n) = 1/(σ√2π)e^-(n-μ)/(2σ²)

P(2) = 1/(1.3693√2π)e^-(2 - 2.5)/(2 (1.875))

P(2) = 33.3%

Pretty good, not great.

You might be interested in
4400 dollars is placed in an account with an annual interest of 8.25%.How much will be in the account after 29 years
SOVA2 [1]
If interest is compounded annually, the account balance will be
.. 4400*1.0825^29 ≈ 43,839.13 . . . . dollars
4 0
3 years ago
Which model represents the product 3/4 x 1/3
dlinn [17]

Answer:

The first one

Step-by-step explanation:

5 0
2 years ago
Calculate the surface area of a hockey puck with a height of 1 in. and a diameter of 3 in
uysha [10]

Answer:

23.56

Step-by-step explanation:

2(\pi r^{2}) + 2\pirh

2(\pi 1.5^{2})+ 2\pi(1.5)(1)

23.56

6 0
3 years ago
What is 3/4 of 16/21? worked out please
timofeeve [1]
Of means multiplication

So

\frac{3}{4} \sf{of}  \frac{16}{21}  =  \frac{3}{4} \times  \frac{16}{21}

And then simplify the numerator ad denominator

= \frac{3 \times 16}{4 \times 21} =  \frac{\ 1 \times 16}{4 \times 7}

And simplify the numerator and denominator again

= \frac{\ 1 \times 16}{4 \times 7} = \frac{\ 1 \times 4}{1 \times 7}

And we are finally left with the answer which is \frac{4}{7}
5 0
3 years ago
Is it true that Terms with no variables are like terms?
oksano4ka [1.4K]

Answer:

yes

Step-by-step explanation:

8 0
2 years ago
Other questions:
  • Plzzz help will give the brainliest for correct answer
    15·2 answers
  • (SAT Prep) Find the value of x.
    15·2 answers
  • 30% of the people shopping walking at Walmart no shoes on . if there are 24 people Walmart with no shoes on how many people are
    13·1 answer
  • You are working on an urban planning project assessing the growth of a city. Five years ago, the population was 134,785 The curr
    15·1 answer
  • What is 2/3 of 90 degrees equal
    13·1 answer
  • Znajdź wszystkie rozwiązania <br>x^4-16=0​
    5·1 answer
  • Your friend's pedometer shows that he took 17000 steps in 2.50 h during a hike. how would the answer change if the time were giv
    13·1 answer
  • I got stuck, I don’t even know where to start I think the answer is A but idk. Help pls
    7·1 answer
  • What is the coefficient of x in 4+3y²+x?
    15·1 answer
  • If a2 -2ab + b2 = 9 and a
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!