The army reports that the distribution of head circumfererence among soldiers is approximately Normal with mean 22.8 inches and standard deviation 1.1 inches. Helmets are mass produced for all except the smallest 5 % and the largest 5 % of head sizes. soldiers in the smallest or largest 5% get custom made helmets. What head sizes get custom-made helmets?
Ok I don't see what I'm doing wrong here
.0500 = 1.1^-1 (x - 22.8)
x = .0500 (1.1) + 22.8
x = 22.855
1 answer