Solve the system using elimination. x − y = 4 −x − y = 6

Find the expected value and the variance of the number of times one must throw a die until the outcome 1 has occurred 5 times.

Kazeer [188]

Answer: E(X) = 30; Var[X] = 180

Step-by-step explanation: This is a Bernoulli Experiment, i.e., the experiment is repeated a fixed number of times, the trials are independents, the only two outcomes are "success" or "failure" and the probability of success remains the same, So, to calculate Expected Value, which is the mean, in these conditions:

$E(X)=\frac{r}{p}$

r is number of times it is repeated

p is probability it happens

Solving:

$E(X)=\frac{5}{1/6}$

E(X) = 30

Variance is given by:

$Var[X]=\frac{r(1-p)}{p^{2}}$

$Var[X]=\frac{5(1-1/6)}{(1/6)^{2}}$

$Var[X]=5.\frac{5}{6}.6^{2}$

Var[X] = 180

Expected Value and Variance of the number of times one must throw a die until 1 happens 5 times are 30 and 180, respectively.

4 0

3 years ago

Can someone help me please....

zhannawk [14.2K]

Answer:

B. 350 minutes

Step-by-step explanation:

7 0

2 years ago

Barry’s Bagel Emporium sells a dozen bagels for $5.00. This price is no longer high enough to create a profit. The owner decides

katen-ka-za [31]

Answer:

Plan C will be the fastest - it will take 10 weeks

Step-by-step explanation:

Plan A will take 60 weeks

Plan B will take the longest 104 weeks

Plan D will be the fastest - it will take 12 weeks

8 0

2 years ago

QUESTION 3 - Distinguish whether the following pairs of events are dependent

TiliK225 [7]

Two eventis are independent if knowledge about the first doesn't change your expectation about the second.

a) Independent: After you know that the first die showed 4, you stille expect all 6 numbers from the second. So, the fact that the first die showed 4 doesn't change your expectation about the second die: it can still show numbers from 1 to 6 with probability 1/6 each.

b) Independent: It's just the same as before. After you know that the first coin landed on heads, you still expect the second coin to land on heads or tails with probability 1/2 each. Knowledge about the first coin changed nothing about your expectation about the second coin.

a) Dependent: In this case, there is a cause-effect relation, so the events are dependent: knowing that a person is short-sighted makes you almost sure that he/she will wear glasses. So, knowledge about being short sighted changed your expectation about wearing glasses.

8 0

3 years ago

It’s question 14 I need help with please it’s due soon

belka [17]

if you are trying to work out -3/4 - (-1/4 - 1/2) then the answer is 0

5 0

3 years ago