A student takes a 48 question multiple choice quiz. The student is unprepared, so they guess on every question. The probability of guessing a correct answer is 1/4. Find the mean and standard deviation for the random variable

Step-by-step explanation:

Given

Number of questions, n = 48

Probability of correct answer, p = 1/4

Required

- Find the mean

- Find the standard deviation

Using probability notations;

n = 48 and p = 1/4

Mean is calculated as follows;

Substitute 48 for n and 1/4 for p

The Mean is 12

Calculating Standard Deviation (SD)

Substitute 48 for n and 1/4 for p

Solve the expression in the bracket

Open Bracket

Take Square Root of 36

The standard deviation is 6

answer:

step-by-step explanation:

here, the total dishes = 10

dishes having meat = 3 ( chicken, meatloaf and hamburger )

thus, the probability of having meat on the chosen dishes = number of dishes having meat / total dishes

=

therefore, the probability of not having meat = 1- the probability of having meat on the chosen dishes

=

=

=

⇒ option b is correct.

answer: input the dimensions of the room to be painted. click the button to calculate the amount of paint and man-hours needed for this job.

interior paint coverage depends on the brand of paint used. the coverage amount is listed on the label of the paint can. use this to adjust the values in the paint coverage section below. paint usually is applied at 350 to 400 square feet per gallon (primer at 200 to 300 square feet per gallon).

step-by-step explanation: