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4 years ago

Can somebody please help me with this question?

Mathematics

1 answer:

meriva4 years ago

7 0

What, this is math right?

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Need help with this Geometry

sukhopar [10]

Answer:

A vertical is an alignment in which the top is always above the bottom. It is a property of two or more points in which if a point is directly below the second point, and they are vertical to each other.

Step-by-step explanation:

pls brain list

7 0

3 years ago

Read 2 more answers

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.

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

7 0

3 years ago

This is fairly easy yet i cannot do this

ICE Princess25 [194]

Answer:

( -9, -6)

Step-by-step explanation:

The red dot is the original (6, 9)

The blue dot is when it is rotated 270 degrees clockwise (-9, -6).

7 0

3 years ago

Purple paint:mix 2 quarts of red paint for every3quarts of blue paint. How many blue paint is needed to make 35 quarts of purple

Phoenix [80]

Answer: 21 quarts of blue paint

Step-by-step explanation: To make a batch of purple paint, it is necessary 2 quarts of red and 3 quarts of blue, resulting in 5 quarts of purple.

So, to make 35 quarts of purple:

5x = 35

x = 7

It is needed, in total, 7 quarts of purple.

As, the ratio is 2 quarts of red to 3 quarts of blue:

Blue: 7 x 3 = 21

For 35 quarts of purple paint, it's necessary 21 quarts of blue paint.

4 0

3 years ago

Find the probability of each event. A class has five boys and nine girls. If the teacher randomly picks six students, what is th

kumpel [21]

Answer: $\dfrac{60}{143}$

Step-by-step explanation:

Given, A class has five boys and nine girls.

Total students = 5+9=14

Number of ways to choose 6 students out of 14= $^{14}C_6$ [Using combinations]

Number of ways to choose 4 girls out of 6 (4 girls + 2 boys = 6 ) = $^{9}C_4\times\ ^{5}C_2$

If the teacher randomly picks six students, then the probability that he will pick exactly four girls:-

$\dfrac{^{9}C_4\times \ ^{5}C_2}{^{14}C_6}$

$=\dfrac{\dfrac{9!}{4!5!}\times\dfrac{5!}{2!3!}}{\dfrac{14!}{6!8!}}\\\\=\dfrac{1260}{3003}\\\\=\dfrac{60}{143}$

hence, the required probability = $\dfrac{60}{143}$ .

4 0

3 years ago