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3 years ago

How many handshakes are possible at a party of 65 people if everyone shakes hands once?

1 answer:

riadik2000 [5.3K]3 years ago

7 0

You must calculate how many ways can 2 people be selected from 65.
The formula is:
n! / r! * (n-r)! =
65! / 2! * 63! =
65*64*63! / 2 * 63! =
65*64 / 2 =
2,080 handshakes

Source:
http://www.1728.org/combinat.htm

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Easton is going to invest $340 and leave it in an account for 8 years. Assuming the interest is compounded quarterly, what inter

Jlenok [28]

Answer:

100.7%

Step-by-step explanation:

Since the interest is compounded quarterly, and there are 4 quarters per year, that would leave us with 32 quarters total where interest is acquired. Now, we need to find the interest rate, that would be required in order to end up with 420 dollars after 32 quarters.

We can setup a formula using our period of time and the money he invested into the bank:

$340(x)^{32}=420$

We can divide 340 from both sides, and simplify the right side to 21 divided by 17:

$x^{32}=\frac{21}{17}$

Taking the 32th root of 21/17 is equal to 1.00662, which is equal to 100.0662%. To the nearest tenth of a percent, this is equal to 100.7%.

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2 years ago

Philip ran out of time while taking a multiple-choice test and plans to guess the last 4 questions. Each question has 5 possible

White raven [17]

Using the binomial distribution, it is found that there is a 0.4096 = 40.96% probability that he answers exactly 1 question correctly in the last 4 questions.

<h3>What is the binomial distribution formula?</h3>

The formula is:

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$C_{n,x} = \frac{n!}{x!(n-x)!}$

The parameters are:

x is the number of successes.

n is the number of trials.

p is the probability of a success on a single trial.

Considering that there are 4 questions, and each has 5 choices, the parameters are given as follows:

n = 4, p = 1/5 = 0.2.

The probability that he answers exactly 1 question correctly in the last 4 questions is P(X = 1), hence:

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 1) = C_{4,1}.(0.2)^{1}.(0.8)^{3} = 0.4096$

0.4096 = 40.96% probability that he answers exactly 1 question correctly in the last 4 questions.

More can be learned about the binomial distribution at brainly.com/question/24863377

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8 0

2 years ago

PLEASE HELP ASAP 20 PTS

Natalija [7]

1. H and E i dont know the rest if I’m being completely honest but there’s the first one for you

7 0

3 years ago

PLEASE HELP!!!:)). The area of the trampezoid is 100dm and the bases are 2.1m and 1.9m. Calculate the height of the trampezoid

mixas84 [53]

Answer:

Well, the only thing you should do is to use the formula.

if the bases are: a, b

and the height is=h

Then, this is your formula, S=½(a+b)×h

Step-by-step explanation:

Aight,

100dm=10m

S=10m

now, the formula

10=½(2.1+1.9)×h===> 20=4h==> h=5m

5 0

3 years ago

In the diagram below, what is the relationship between the number of triangles and the perimeter?

Eduardwww [97]

The perimeter "P" is equal to the length of the base of one triangle multiplied by the "n" number of triangles in the figure plus two times the length of another side. The equation for the perimeter is P = 5n + 14.

We are given triangles. The triangles are arranged in a certain pattern. The length of the base of each triangle is equal to 5 units. The length of the other two sides is 7 units each. We conclude that all the triangles are isosceles. We need to find the relationship between the number of triangles and the perimeter of the figure. Let the perimeter of the figure having "n" number of triangles be represented by the variable "P".

P(1) = 14 + 5(1)

P(2) = 14 + 5(2)

P(3) = 14 + 5(3)

We can see and continue the pattern. The relationship between the perimeter and the number of triangles is given below.

P(n) = 14 + 5n

To learn more about perimeter, visit :

brainly.com/question/6465134

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1 year ago