2. While NEEDS and WANTS can vary greatly depending on the individual and their situation, which of these items

A university found that of its students withdraw without completing the introductory statistics course. Assume that students reg

polet [3.4K]

Answer:

A university found that 30% of its students withdraw without completing the introductory statistics course. Assume that 20 students registered for the course.

a. Compute the probability that 2 or fewer will withdraw (to 4 decimals).

= 0.0355

b. Compute the probability that exactly 4 will withdraw (to 4 decimals).

= 0.1304

c. Compute the probability that more than 3 will withdraw (to 4 decimals).

= 0.8929

d. Compute the expected number of withdrawals.

= 6

Step-by-step explanation:

This is a binomial problem and the formula for binomial is:

$P(X = x) = nCx p^{x} q^{n - x}$

a) Compute the probability that 2 or fewer will withdraw

First we need to determine, given 2 students from the 20. Which is the probability of those 2 to withdraw and all others to complete the course. This is given by:

$P(X = x) = nCx p^{x} q^{n - x}\\P(X = 2) = 20C2(0.3)^2(0.7)^{18}\\P(X = 2) =190 * 0.09 * 0.001628413597\\P(X = 2) = 0.027845872524$

$P(X = x) = nCx p^{x} q^{n - x}\\P(X = 1) = 20C1(0.3)^1(0.7)^{19}\\P(X = 1) =20 * 0.3 * 0.001139889518\\P(X = 1) = 0.006839337111$

$P(X = x) = nCx p^{x} q^{n - x}\\P(X = 0) = 20C0(0.3)^0(0.7)^{20}\\P(X = 0) =1 * 1 * 0.000797922662\\P(X = 0) = 0.000797922662$

Finally, the probability that 2 or fewer students will withdraw is

$P(X = 2) + P(X = 1) + P(X = 0) \\= 0.027845872524 + 0.006839337111 + 0.000797922662\\= 0.035483132297\\= 0.0355$

b) Compute the probability that exactly 4 will withdraw.

$P(X = x) = nCx p^{x} q^{n - x}\\P(X = 4) = 20C4(0.3)^4(0.7)^{16}\\P(X = 4) = 4845 * 0.0081 * 0.003323293056\\P(X = 4) = 0.130420974373\\P(X = 4) = 0.1304$

c) Compute the probability that more than 3 will withdraw

First we will compute the probability that exactly 3 students withdraw, which is given by

$P(X = x) = nCx p^{x} q^{n - x}\\P(X = 3) = 20C3(0.3)^3(0.7)^{17}\\P(X = 3) = 1140 * 0.027 * 0.002326305139\\P(X = 3) = 0.071603672205\\P(X = 3) = 0.0716$

Then, using a) we have that the probability that 3 or fewer students withdraw is 0.0355+0.0716=0.1071. Therefore the probability that more than 3 will withdraw is 1 - 0.1071=0.8929

d) Compute the expected number of withdrawals.

E(X) = 3/10 * 20 = 6

Expected number of withdrawals is the 30% of 20 which is 6.

5 0

3 years ago

Evaluate 14+ (- 2)<br> A) 12<br> B)- 12<br> C) 16<br> D)- 16

11111nata11111 [884]

The answer would be A.12

6 0

3 years ago

I will give Brainiest if you are right

Vadim26 [7]

Answer:

19.5º

Step-by-step explanation:

Every triangle is equal to 180º for all angles. So, you add 33.5 + 127 and subtract the sum by 180.

33.5 + 127= 160.5

180- 160.5 = 19.5

So, the angle F is 19.5º

Hope this helps !!

-Ketifa

8 0

2 years ago

Read 2 more answers

Use the distributive property to write an expression that is equivalent to each given property.

Nadya [2.5K]

Answer:

-6x+12

-9+5a

7x+63

8y-4/5x-12

Step-by-step explanation:

To solve these all you have to do is take the number outside of the parenthesis and multiply them by each term.

-3(2x)-3(-4) All I did here was expand the problem to show what i mean by terms.

-6x+12

Do this for each problem.

0.1(-90)+0.1(50a)

-9+5a

-7(-x)-7(-9) For this one you are taking negatives times negatives so each answer will be positive.

7x+63

4/5(10y)+4/5(-x)+4/5(-15)

8y-4/5x-12

3 0

3 years ago

[final due to glitching] find the value of x for this parallelogram

Butoxors [25]

Answer:

x = 0

Step-by-step explanation:

both angles equal each other

I hope this helps

5 0

2 years ago