Question

Records suggest that the normal distribution with mean 50 and standard deviation 8 is a plausible model for a measurement of the amount of people in a subway coach. Find P[41.2 ≤ X ≤ 43.04].

Answer 1

Solution :

Given that ,

mean = = 50

standard deviation = = 8

= P[(41.2 - 50 / 8) (x - ) / (43.04 - 50 / 8) ]

= P -1.1 z -0.87)

= P(z -0.87) - P(z -1.1)

= 0.1922 - 0.1357

= 0.0565

P()P[41.2 X 43.04] = 0.0565