# Incomes in two particular neighborhoods follow normal distribution.

QUESTION: Example: Family incomes in two particular neighborhoods follow a normal distribution. For Neighborhood 1 the mean is \$26,500, with a standard deviation of \$15,000. For Neighborhood 2, the mean is \$30,000 with a standard deviation of \$18,000.

A) What proportion of families in Neighborhood 1 have incomes below the mean family income in Neighborhood 2?

B) What income level in Neighborhood 1 represents the top 10% for that neighborhood?

C) What income level for neighborhood 2 represents the lowest 5% of incomes for that neighborhoods?

D) For neighborhood 1, what percentage of families have incomes that fall between the mean incomes of Neighborhood 1 and neighborhood 2?

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...ore; Z = (30,000-26,500)/STD 1
= .2333
Therefore Prob = .5922 ( from Normal Table for corresponding Z value)

B)Top 10% means 90% must be below this income figure X.
There Z score is given in this ...