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terp_in_umcp
Students
 
Posts: 4
Joined: Sat Sep 11, 2010 4:03 am
 

Statistics Population Problem

by terp_in_umcp Mon May 30, 2011 1:03 am

How do you approach such a problem where the actual values are not given?

An insurance company is interested in a statistical profile of the age its clients in a particular geographic region. They provide you with grouped data on all (i.e. the population) of their clients in that region:

Code: Select All Code
Age                             Number
Less than 25 years old             20
25 years old to 34.99 years old    40
35 years old to 49.99 years old    50
50 years old to 64.99 years old    50
65 plus years old                  30

Required

1. Calculate the mean age of the company’s clients in this region
2. Calculate the median age of the company’s clients in this region
3. Calculate the variance and standard deviation of the clients’ age in this region
4. Calculate the 25th and 75th percentile of the clients’ age.
jnelson0612
ManhattanGMAT Staff
 
Posts: 2664
Joined: Fri Feb 05, 2010 10:57 am
 

Re: Statistics Population Problem

by jnelson0612 Mon May 30, 2011 1:46 am

I really don't think you can get exact answers here; you would be answering in terms of bands of ages. For example, we can figure out what age band contains the median age, but we can't determine exactly what that age is.
Jamie Nelson
ManhattanGMAT Instructor