1. the random variable X~N(800, 625) is linearly transformed into X = 400 + 2X. The probability P (Y<1950) is (rounded):

a) 0.0228

b) 0.0456

c) 0.0971

d) 0.1295

e) 0.1587 (correct solution, but how does the calculation work?)

4 A random sample of size n = 25 is drawn from X~N(800, 625) and the arithmetic mean X-stroke is calculated. Which rounded value of X dash is not exceeded with 95% probability?

a) 808.22 (correct solution, but how does the calculation work?)

b) 810.76

c) 815.93

d) 818.87

e) 823.91