b)
for normal distribution z score =(X-μ)/σx | |
mean μ= | 1.8 |
standard deviation σ= | 0.7 |
sample size =n= | 6 |
standard error=(σ/√n)*√(N-n)/(N-1))= | 0.7000 |
probability =P(1<X<2)=P((1-1.8)/0.286)<Z<(2-1.8)/0.286)=P(-2.8<Z<0.7)=0.758-0.0026=0.7554 |
c)
probability =P(1<X<2)=P((1-1.8)/0.143)<Z<(2-1.8)/0.143)=P(-5.6<Z<1.4)=0.9192-0=0.9192 |
d)
yes
the standard deviation decreases as n increases
e)
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