Question

A. Use Minitab Express to construct a standard normal distribution to find the proportion of the curve above z = 2.50. Copy+paste your distribution here and clearly identify your final answer. Please show a screenshot of your minitab screen.

B. Use Minitab Express to construct a normal distribution with a mean of 500 and standard deviation of 100 and find the area above x = 750. Copy+paste your distribution here and clearly identify your final answer. Please show a screenshot of your minitab screen.

C. Explain why your answers to A and B are the same.

Answer 1

The probability that Z > 2.50 is equal to the blue area under the curve. 0.5 0.4 0.3 y 0.2 0.1 0.0 2.5 -0.1 -4 -3 -2 -1 0 1 2 3 4. Х Step 2: To find the area above 2.50, first we will find the area below 2.50 (the white one).

Blue area = 1 - white area = 1 - 0.9938 = 0.0062 Last statement can be writed in math notationa as:
B-

The probability that X > 750 is equal to the blue area under the curve. 0.005 0.004 0.003 y 0.002 ^ 0.001 0.000 750 -0.001 100 200 300 400 500 600 700 800 900 x Step 2: Since u 500 and 0 = 100 we have: P(X > 750 ) = P(X-u > 750 – 500 Since Z = 2-4 and 750-500 100 - 2.5 we = have:

P(X > 750 ) = P(Z > 2.5) Step 3: Use the standard normal table to conclude that: P(Z > 2.5) = 0.0062
3- because both have same z-score.