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GenaCL600 [577]

2 years ago

7

To determine whether students at Bernal want to attend an art festival at the school, Manuel surveys all the students in the lib

rary at lunch.
Biased or unbiased. Explain for brainlist, no links or report.

1 answer:

jeka942 years ago

3 0

Biased- selection bias

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What is the difference of 13.2 - 6.56

vichka [17]

Answer:

6.64

Step-by-step explanation:

Subtract : 13.2 - 6.56

13.2(0)

-6.56

----------

6.64

8 0

3 years ago

Read 2 more answers

Q²-19q+84=0<br><br>what may the answer be?(testing app with random question)

aleksandr82 [10.1K]

The answer may be 7 or 12

5 0

3 years ago

Suppose that 50% of all young adults prefer McDonald's to Burger King when asked to state a preference. A group of 12 young adul

ddd [48]

Answer:

a) 0.194 = 19.4% probability that more than 7 preferred McDonald's

b) 0.787 = 78.7% probability that between 3 and 7 (inclusive) preferred McDonald's

c) 0.787 = 78.7% probability that between 3 and 7 (inclusive) preferred Burger King

Step-by-step explanation:

For each young adult, there are only two possible outcomes. Either they prefer McDonalds, or they prefer burger king. The probability of an adult prefering McDonalds is independent from other adults. So we use the binomial probability distribution to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

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

In which $C_{n,x}$ is the number of different combinations of x objects from a set of n elements, given by the following formula.

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

And p is the probability of X happening.

50% of all young adults prefer McDonald's to Burger King when asked to state a preference.

This means that $p = 0.5$

12 young adults were randomly selected

This means that $n = 12$

(a) What is the probability that more than 7 preferred McDonald's?

$P(X > 7) = P(X = 8) + P(X = 9) + P(X = 10) + P(X = 11) + P(X = 12)$

In which

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

$P(X = 8) = C_{12,8}.(0.5)^{8}.(0.5)^{4} = 0.121$

$P(X = 9) = C_{12,9}.(0.5)^{9}.(0.5)^{3} = 0.054$

$P(X = 10) = C_{12,10}.(0.5)^{10}.(0.5)^{2} = 0.016$

$P(X = 11) = C_{12,11}.(0.5)^{11}.(0.5)^{1} = 0.003$

$P(X = 12) = C_{12,12}.(0.5)^{12}.(0.5)^{0} = 0.000$

$P(X > 7) = P(X = 8) + P(X = 9) + P(X = 10) + P(X = 11) + P(X = 12) = 0.121 + 0.054 + 0.016 + 0.003 + 0.000 = 0.194$

0.194 = 19.4% probability that more than 7 preferred McDonald's

(b) What is the probability that between 3 and 7 (inclusive) preferred McDonald's?

$P(3 \leq X \leq 7) = P(X = 3) + P(X = 4) + P(X = 5) + P(X = 6) + P(X = 7)$

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

$P(X = 3) = C_{12,3}.(0.5)^{3}.(0.5)^{9} = 0.054$

$P(X = 4) = C_{12,4}.(0.5)^{4}.(0.5)^{8} = 0.121$

$P(X = 5) = C_{12,5}.(0.5)^{5}.(0.5)^{7} = 0.193$

$P(X = 6) = C_{12,6}.(0.5)^{6}.(0.5)^{6} = 0.226$

$P(X = 7) = C_{12,7}.(0.5)^{7}.(0.5)^{5} = 0.193$

$P(3 \leq X \leq 7) = P(X = 3) + P(X = 4) + P(X = 5) + P(X = 6) + P(X = 7) = 0.054 + 0.121 + 0.193 + 0.226 + 0.193 = 0.787$

0.787 = 78.7% probability that between 3 and 7 (inclusive) preferred McDonald's

(c) What is the probability that between 3 and 7 (inclusive) preferred Burger King?

Since $p = 1-p = 0.5$ , this is the same as b) above.

So

0.787 = 78.7% probability that between 3 and 7 (inclusive) preferred Burger King

7 0

2 years ago

Find the area of the triangle.

Vsevolod [243]

Answer:

20 m²

Step-by-step explanation:

<u>Formula (Area of triangle):</u>

<u /> $\text{A (Triangle)} = \dfrac{1}{2} \times \text{Base} \times \text{Height}$

From the triangle, we can see that the base of the triangle is "7 + 3" m and the height of the triangle is "4" m.

<u /> $\implies \text{A (Triangle)} = \dfrac{1}{2} \times (7 + 3) \times (4)$

Simplify the right-hand-side as needed to evaluate the area.

<u /> $\implies \text{A (Triangle)} = \dfrac{1}{2} \times (10) \times (4)$

<u /> $\implies \text{A (Triangle)} = \dfrac{40}{2} = 20 \ \text{m}^{2}$

Therefore, the area of the provided triangle is 20 m².

Learn more about this topic: brainly.com/question/15442893

8 0

2 years ago

Find AC<br>I'd appreciate any help!

Digiron [165]

5

Explanation:
2 - (-3) = 5

6 0

2 years ago