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

x ≥ 18 is your answer

step-by-step explanation:

let "a number" = x

(2/3)x + 17 ≥ 29

isolate the variable (x). do the opposite of pemdas (parenthesis, exponent (& root), multiplication, division, addition, subtraction).

first, subtract 17 from both sides.

(2/3)x + 17 (-17) ≥ 29 (-17)

(2/3)x ≥ 29 - 17

(2/3)x ≥ 12

next, multiply 3/2 to both sides to isolate the x

(3/2)(2/3)x ≥ 12(3/2)

x ≥ 12(3/2)

simplify. multiply, then divide

x ≥ (12 * 3)/2

x ≥ (36)/2

x ≥ 18

x ≥ 18 is your answer

~

idk

step-by-step explanation: