Answer:
Step-by-step explanation:
a.) it's just mean, variance
so here it's just 12,6.25
b.) For the x bar thing just divide the variance by the number of people (mean stay the same)
the variance is then (2.5²/34)= .1838
which makes it (12,.1838)
c.) here we don't use x bar (and so it's normal (12,2.5²))
p(11.6) = (11.6-12)/(2.5)= -.16 = .4364
p(12.4)= (12.4-12)/2.5 = .16= .5636
.5636-.4364= .1272
d.) here we use x bar because it's asking for an average so it's normal (12, .1838)
same deal
p(11.6)=(11.6-12)/√.1838= -.93295= .1762
p(12.4)= (12.4-12)/√.1838= .93295= .8238
.8238-.1762= .6476
d.) no because they're probably IID
f.) It's average so here we use x bar
q1 is just the 25th percentile
the 25th percentile is -.6745
-.6745=(x-12)/(√.1838)= 11.711
q3 is the 75th percentile
.6745=(x-12)/√.1838
x=12.289
The interquartile range is just the difference between the two
12.289-11.711= .5784
