Page 63 - Math SL HB Sem 3
P. 63
The thickness of paper produced by a factory has a normal distribution of mean ol lmmand standard
deviation ol o.03mm.2.1o/o of the paper has thickness less than k mm.
Find the value of ft.
\. solution:
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)Finding p (Paper 1 Question cannot be solved by GDC):
\. Example:
The weights of people living in city A are normally distributed with a standard deviation of I kg.
The probability of a person randomly chosen that weighs heavier than 58kg is 0.31S.
a) Find the mean weight of the population in city A.
b) Calculate the probability of a person being lighter than SSkg.
\ sotution:
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) Finding o (Paper 1 Question cannot be solved by GDC):
\ Exampte:
Factory A produces chocolate bars with mean weight of 25 grams. It is assumed that the
weights ofthe products are normafly distributed and upon product inspection, 5 %o ofthe chocorate
bars weigh less than 22 grams.
Find the standard deviation of the weight of the chocolate bar.
2.1
