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There are two games involving flipping a coin. In the first game you win a prize if you can throw between 45% and 55% heads. In

Nina [5.8K]

Answer:

d) 300 times for the first game and 30 times for the second

Step-by-step explanation:

We start by noting that the coin is fair and the flip of a coin has a probability of 0.5 of getting heads.

As the coin is flipped more than one time and calculated the proportion, we have to use the sampling distribution of the sampling proportions.

The mean and standard deviation of this sampling distribution is:

$\mu_p=p\\\\ \sigma_p=\sqrt{\dfrac{p(1-p)}{N}}$

We will perform an analyisis for the first game, where we win the game if the proportion is between 45% and 55%.

The probability of getting a proportion within this interval can be calculated as:

$P(0.45$

referring the z values to the z-score of the standard normal distirbution.

We can calculate this values of z as:

$z_H=\dfrac{p_H-\mu_p}{\sigma_p}=\dfrac{(p_H-p)}{\sqrt{\dfrac{p(1-p)}{N}}}=\sqrt{\dfrac{N}{p(1-p)}}*(p_H-p)>0\\\\\\z_L=\dfrac{p_L-\mu_p}{\sigma_p}=\dfrac{p_L-p}{\sqrt{\dfrac{p(1-p)}{N}}}=\sqrt{\dfrac{N}{p(1-p)}}*(p_L-p)$

If we take into account the z values, we notice that the interval increases with the number of trials, and so does the probability of getting a value within this interval.

With this information, our chances of winning increase with the number of trials. We prefer for this game the option of 300 games.

For the second game, we win if we get a proportion over 80%.

The probability of winning is:

$P(p>0.8)=P(z>z^*)$

The z value is calculated as before:

$z^*=\dfrac{p^*-\mu_p}{\sigma_p}=\dfrac{p^*-p}{\sqrt{\dfrac{p(1-p)}{N}}}=\sqrt{\dfrac{N}{p(1-p)}}*(p^*-p)>0$

As (p*-p)=0.8-0.5=0.3>0, the value z* increase with the number of trials (N).

If our chances of winnings depend on P(z>z*), they become lower as z* increases.

Then, we can conclude that our chances of winning decrease with the increase of the number of trials.

We prefer the option of 30 trials for this game.

8 0

3 years ago

Find all real solutions of the equation. (if there is no real solution, enter no real solution.) 35x2 12x − 36

solmaris [256]

Important: 35x2 12x − 36 is not an equation; to obtain an equation, you must set 35x2 12x − 36 = to 0:

35x^2 + 12x − 36 = 0. Also, "the square of x" must be represented by "x^2," and you must insert either the + or the - sign in front of the term 12x.

I am assuming that you meant 35x^2 + 12x − 36 = 0.

If that is indeed the case, then a = 35, b = 12 and c = -36

and the discriminant is b^2 - 4ac, or (12)^2 - 4(35)(-36) = 5184.

Since the discriminant is positive, this equation has 2 real, unequal solutions. They are
-12 plus or minus sqrt(5184)
x = -----------------------------------------
2(35)

7 0

3 years ago

1. Evaluate the expression: 4 – 3s2 + (s + t) for t = -2 and s = 5

den301095 [7]

Answer:The Answer is -23

Step-by-step explanation:

7 0

3 years ago

Please help this is my 3rd time asking :(

Ainat [17]

Answer:

$6

Step-by-step explanation:

She bought a toy for 4 dollars, so we need to subtract that from 88. This gives us 84 dolalrs. She bought 8 shirts and 6 pants, which is 14 items total. Divide 88 by 14 and you get 6.

Hope that helps :)

4 0

2 years ago

Read 2 more answers

Use the diagram to find the measure of

mixer [17]

Answer:

44°

Step-by-step explanation:

m∠MKN=44° (sum of angles in a triangle)

m∠KMJ=44° (definition of congruent angles)

3 0

2 years ago