Question

1.

X has a normal distribution with the given mean and standard deviation. Find the indicated probability. (Round your answer to four decimal places.) μ = 41, σ = 20, find P(35 ≤ X ≤ 42)

2. Find the probability that a normal variable takes on values within 0.9 standard deviations of its mean. (Round your decimal to four decimal places.)

3. Suppose X is a normal random variable with mean μ = 100 and standard deviation σ = 10. Find a such that

P(X ≥ a) = 0.03.

(Round your answer to one decimal place.)
a = _______

Answer 1