Need help bad don't know how to solve. I don't get this math at all!

Tennis Replay In the year that this exercise was written, there were 879 challenges made to referee calls in professional tennis

tiny-mole [99]

Answer:

a. 0.0209 = 2.09% probability that among the 879 challenges, the number of overturned calls is exactly 231.

b. 231 is less than 2.5 standard deviations above the mean, which means that 231 overturned calls among 879 challenges is not a significantly high result.

Step-by-step explanation:

For each challenge, there are only two possible outcomes. Either it was overturned, or it was not. The probability of a challenge being overturned is independent of any other challenge. This means that the binomial probability distribution is used 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.

Significantly high:

The expected value of the binomial distribution is:

$E(X) = np$

The standard deviation of the binomial distribution is:

$\sqrt{V(X)} = \sqrt{np(1-p)}$

If a value is more than 2.5 standard deviations above the mean, this value is considered significantly high.

25% of the challenges are successfully upheld with the call overturned.

This means that $p = 0.25$

879 challenges

This meas that $n = 879$

a. If the 25% rate is correct, find the probability that among the 879 challenges, the number of overturned calls is exactly 231.

This is P(X = 231). So

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

$P(X = 231) = C_{879,231}.(0.25)^{231}.(0.75)^{648} = 0.0209$

0.0209 = 2.09% probability that among the 879 challenges, the number of overturned calls is exactly 231.

b. If the 25% rate is correct, find the probability that among the 879 challenges, the number of overturned calls is 231 or more. If the 25% rate is correct, is 231 overturned calls among 879 challenges a result that is significantly high

The mean is:

$E(X) = np = 879*0.25 = 219.75$

The standard deviation is:

$\sqrt{V(X)} = \sqrt{np(1-p)} = \sqrt{879*0.25*0.75} = 12.84$

$219.75 + 2.5*12.84 = 251.85 > 231$

231 is less than 2.5 standard deviations above the mean, which means that 231 overturned calls among 879 challenges is not a significantly high result.

5 0

3 years ago

Write an algebraic expression that models the word phrase "the product of 8 and the sum of a number X and 3"

Leya [2.2K]

The answer is d.
8(x+3)

4 0

3 years ago

What the answer now

stiks02 [169]

Answer:

35.6 yd²

Step-by-step explanation:

Area of ∆UVW can be solved if we know the lengths of 2 sides and their included angle.

We are Given just 1 side, UV (w). Use the law of sines to find UW (v).

Thus:

$\frac{v}{sin(V)} = \frac{w}{sin(W)}$

W = 137°

w = 19 yd

V = 180 - (137 + 22) = 21° => sum of triangle

v = ??

Plug in the values and solve for v

$\frac{v}{sin(21)} = \frac{19}{sin(137)}$

Multiply both sides by sin(21)

$\frac{v}{sin(21)}*sin(21) = \frac{19}{sin(137)}*sin(21)$

$v = \frac{19*sin(21)}{sin(137)}$

$v = 10 yd$ (approximated)

Find area of ∆UVW:

Area = ½*UV*UW*sin(U)

Area = ½*v*w*sin(U)

= ½*10*19*sin(22)

Area = 35.6 yd² (to nearest tenth)

7 0

3 years ago

How do you write 3 7/10 as a decimal

Leokris [45]

Answer:

3.7

Step-by-step explanation:

To change a fraction to a decimal, just divide the numerator with the denominator. Instead of placing the remainder over the divisor, continue to solve until it is answered (unless it's a repeating decimal.)

Divide 7 with 10:

7/10 = 0.7

Remember that there is a whole number, 3. Add that to the decimal you have gotten:

3 + 0.7 = 3.7

3.7 is your answer.

~

8 0

3 years ago

PLEASE HELP ASAP WILL GIVE BRAINLIEST

Digiron [165]

Answer:

6 mm slope 3

Step-by-step explanation:

4 0

3 years ago