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
GenaCL600 [577]
3 years ago
11

A club of twenty students wants to pick a three person subcommittee. How many ways can this be done?

Mathematics
1 answer:
natulia [17]3 years ago
8 0

1140 ways are there to select three person subcommittee from a club of twenty students

<em><u>Solution:</u></em>

Given that a club of twenty students wants to pick a three person subcommittee

To find: number of ways this can be done

We have to use combinations formula to solve the given sum

A combination is a selection of all or part of a set of objects, without regard to the order in which objects are selected

<em><u>The formula to calculate combinations is:</u></em>

n C_{r}=\frac{n !}{(n-r) ! r !}

where n represents the number of items, and r represents the number of items being chosen at a time

<em><u>Here we have to choose 3 persons from 20 students</u></em>

So, n = 20 and r = 3

\begin{aligned}&20 C_{3}=\frac{20 !}{(20-3) ! 3 !}\\\\&20 C_{3}=\frac{20 !}{17 ! 3 !}\end{aligned}

<em><u>To get the factorial of a number n ,the given formula is used, </u></em>

n !=n \times(n-1) \times(n-2) \dots \times 2 \times 1

Therefore,

20 C_{3}=\frac{20 \times 19 \times 18 \times 17 \ldots \ldots \ldots 2 \times 1}{17 \times 16 \times 15 \ldots .2 \times 1 \times 3 !}

20 C_{3}=\frac{20 \times 19 \times 18}{3 !}=\frac{20 \times 19 \times 18}{3 \times 2 \times 1}=1140

Thus 1140 ways are there to select three person subcommittee from a club of twenty students

You might be interested in
Write a sentence to compare 1000000 using the words 10 times as many
erik [133]
You can write 1000000 is 10 times as many then 100000
7 0
3 years ago
There are 3 white marbles and 7 blue marbles in a bag. Jamie will randomly pick two marbles out of the bag without replacing the
ELEN [110]

Answer:

1/7 is the probability hope this helps


5 0
3 years ago
Read 2 more answers
In a random sample of fivefive microwave​ ovens, the mean repair cost was ​$75.0075.00 and the standard deviation was ​$13.0013.
Radda [10]
<h2>Answer with explanation:</h2>

As per given , we have

Sample size : n= 5

Degree pf freedom = : df= 5-1=4

\mu=\$75.00

\sigma=\$13.00

Significance level for 90% confidence = \alpha=1-0.90=0.1

Using t-value table , t-critical value for 90% confidence:

t_{\alpha/2, df}=t_{0.05, 4}=2.132.

Margin of error of \mu: E=t_{\alpha/2}\dfrac{\sigma}{\sqrt{n}}\\\\(2.132)\dfrac{13}{\sqrt{5}}=12.3949720129\approx12.39

Interpretation : The repair cost will be within $12.39 of the real population mean value \mu 90% of the time.

7 0
3 years ago
I just need an answer, it's my last question.
GrogVix [38]
It's D i just took the test, I'm sure of it

3 0
3 years ago
Solve |x+2| &gt;5-(x-1)^2 by graphing
Anna35 [415]

Answer:

x

<

−

1

or

x

>

2

Step-by-step explanation:

7 0
3 years ago
Other questions:
  • Can someone help me please
    7·2 answers
  • 2a-3b=4, solve for b
    8·2 answers
  • A random sample of 16 students selected from the student body of a large university had an average age of 25 years and a standar
    11·1 answer
  • Find the equation of a line passing through the point (6,−5) and parallel to the line y = 7x + 1. answers : y = 7x − 47 y = −17x
    11·1 answer
  • Convert 3cm to inches
    14·1 answer
  • Identify the focus, directrix, and axis of symmetry of 11x=y^2
    14·1 answer
  • Plz help me well mark brainliest if correct!!.....
    11·2 answers
  • Hello ..........................................................
    11·2 answers
  • SOMEONE PLEASE HELP ME I’m really confused
    12·1 answer
  • √(2x-5)=1+√(x-3)
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!