The average height

Question

The average height of adult males is 70 inches with a standard deviation of 2.4 inches. If the heights are normally distributed, how high should a doorway be such that 95% of all men can pass through the doorway without hitting their heads

Answer 1

 

Z=1.645 =  (X - 70 )/2.4

 

 

X = 1.645*2.4+70 = 73.948

 

 6 feet 4 inches