Let X denote the score of an exam and suppose follows a normal distribution with mean 50 and standard deviation 3. Suppose of a big group of students took this exam. (a) What is the 25th percentile of their score? You may use the fact that the 25th percentile of a standard normal random variable, Z is -0.674. (b) What is the percentage of students whose scores are between 47 and 59? Note that for a standard normal random variable Z, Φ(3) = P(Z ≤ 3) = 0.999 and Φ(1) = P(Z ≤ 1) = 0.841. (c) What is E(X2 )?

infinitely many solutions

step-by-step explanation:

we have been given the equation;

2(2x + 3) = -4 + 2(2x + 5)

we need to determine the value of x.

2(2x + 3), we expand this expression to obtain 4x + 6

similarly 2(2x + 5) will become 4x + 10

now we have;

4x + 6 = -4 + 4x + 10

4x + 6 = 4x + 10 - 4

4x + 6 = 4x + 6

the expression on the left hand side is identical to the one on the right hand side. therefore, we are looking at just a single straight line whose equation is;

y = 4x + 6

consequently, we shall have infinitely many solutions

im guessing (23,14). hope this : )

there is no picture in order for this question to be answered

answer is b chief keef

get this one right