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3 years ago

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A chess club with 80 members is electing a new president. Elsa received 64 votes. What percentage of the club members voted for

Elsa?

1 answer:

hjlf3 years ago

5 0

Answer:

80%

Step-by-step explanation:

You might be interested in

According to government data, 20% of employed women have never been married. If 10 employed women are selected at random, what i

Ierofanga [76]

Answer:

a) $P(X=2) = (10C2) (0.2)^2 (1-0.2)^{10-2}= 0.302$

b) $P(X\leq 2) = P(X=0) + P(X=1) +P(X=2)$

$P(X=0) = (10C0) (0.2)^0 (1-0.2)^{10-0}= 0.107$

$P(X=1) = (10C1) (0.2)^1 (1-0.2)^{10-1}= 0.268$

$P(X=2) = (10C2) (0.2)^2 (1-0.2)^{10-2}= 0.302$

And replacing we got:

$P(X\leq 2) = 0.107+0.268+0.302=0.678$

c) For this case we want this probability:

$P(X\geq 8) = P(X=8) + P(X=9) +P(X=10)$

But for this case the probability of success is p =1-0.2= 0.8

We can find the individual probabilities and we got:

$P(X=8) = (10C8) (0.8)^8 (1-0.8)^{10-8} =0.302$

$P(X=9) = (10C9) (0.8)^9 (1-0.8)^{10-9} =0.268$

$P(X=10) = (10C10) (0.8)^{10} (1-0.8)^{10-10} =0.107$

And replacing we got:

$P(X \geq 8) = 0.677$

And replacing we got:

$P(X\geq 8)=0.0000779$

Step-by-step explanation:

Previous concepts

The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".

Let X the random variable of interest, on this case we now that:

$X \sim Bin (n=10 ,p=0.2)$

The probability mass function for the Binomial distribution is given as:

$P(X)=(nCx)(p)^x (1-p)^{n-x}$

Where (nCx) means combinatory and it's given by this formula:

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

Solution to the problem

Let X the random variable "number of women that have never been married" , on this case we now that the distribution of the random variable is:

$X \sim Binom(n=10, p=0.2)$

Part a

We want to find this probability:

$P(X=2)$

And using the probability mass function we got:

$P(X=2) = (10C2) (0.2)^2 (1-0.2)^{10-2}= 0.302$

Part b

For this case we want this probability:

$P(X\leq 2) = P(X=0) + P(X=1) +P(X=2)$

We can find the individual probabilities and we got:

$P(X=0) = (10C0) (0.2)^0 (1-0.2)^{10-0}= 0.107$

$P(X=1) = (10C1) (0.2)^1 (1-0.2)^{10-1}= 0.268$

$P(X=2) = (10C2) (0.2)^2 (1-0.2)^{10-2}= 0.302$

And replacing we got:

$P(X\leq 2) = 0.107+0.268+0.302=0.678$

Part c

For this case we want this probability:

$P(X\geq 8) = P(X=8) + P(X=9) +P(X=10)$

But for this case the probability of success is p =1-0.2= 0.8

We can find the individual probabilities and we got:

$P(X=8) = (10C8) (0.8)^8 (1-0.8)^{10-8} =0.302$

$P(X=9) = (10C9) (0.8)^9 (1-0.8)^{10-9} =0.268$

$P(X=10) = (10C10) (0.8)^{10} (1-0.8)^{10-10} =0.107$

And replacing we got:

$P(X \geq 8) = 0.677$

3 0

3 years ago

Two cars start from the same point driving in opposite directions. Both cars drive 6miles. One car stops, the other car makes a

dimaraw [331]

Answer:

<u>14.4 mile</u>²

Explanation:

1. By driving 6 miles each, the cars will be 6 miles + 6 miles = 12 miles appart.

2. When one car stops and the other car makes a 90° left-hand turn and drive 8 miles, you can model the situation with a right triangle, where one leg is 12 miles, the other leg is 8 miles, and the hypotenuse is the distance that separates the cars.

Hence, you must use Pythagoras to find that distance.

3. Pythagoras

hypotenuse² = leg₁² + leg₂²

hypotenuse = (12 mile)² + (8 mile)² = 144 mile² + 64 mile² = 208 mile²

$hypotenuse=\sqrt{208mile^2}=14.4mile^2$ , which is rounded to the neartest tenth of a mile.

8 0

3 years ago

A bag contains 5 red marbles, 8 blue marbles and 6 green marbles. If three marbles are drawn out of the bag, what is the probabi

Gala2k [10]

70000000000 + 8818282828828

8 0

3 years ago

What is the positive square root of 0.25

Mrrafil [7]

$\sqrt{0.25} = 0.5 \: or \: - 0.5$
Positive square root of 0.25 = 0.5

Hope this helps. - M

7 0

3 years ago

Read 2 more answers

Please only answer if you're confident.

lina2011 [118]

Answer: ∠B=70°

Step-by-step explanation:

It is shown in the diagram that ∠A and ∠B is vertical angles.

Vertical angle theorem: opposite angles are congruent.

<u>Solve:</u>

∠A=∠B

8x+6=4x+38

4x=32

x=8

<h2>∠B=4x+38=4(8)+38=32+38=70°</h2>

4 0

3 years ago

Read 2 more answers