If the mean height of a group of students equals 170cm with a standard deviation of 10 cm, then the probability that a student is between 160cm and 180cm is .
Mean = 170 cm
Standard deviation = 10 cm
"P(160<X<180)=P(\\frac{160-170}{10}<Z<\\frac{180-170}{10})"
"P(160<X<180)=P(-1<Z<1)"
From Z normal distribution table, it is found that
"P(160<x<180)=P(Z<1)-P(Z<-1)"
"P(160<x<180)=0.8413-0.1586=0.6827"
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