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agumble
05-01-2008, 08:11 AM
The problem states:

What is the probability of finding a home in the USA advertised on this website that is less than $100,000 or under 2000 square feet?

(At this point, we have a chart with data in it. The data is represented in thousands of dollars)

Chart
Prices------------------- Less than 2000 sq. Feet ----------------------2000 sq. ft or more ------------------totals
__________________________________________________ _________________________________________
less then 100 ----------------------13 -------------------------------------------- 3 ----------------------------------16
Between 100 and 300 -------------92 --------------------------------------------42 --------------------------------- 134
More than 300-----------------------5 --------------------------------------------45 ------------------------------------50
__________________________________________________ ________________________________________
Totals ----------------------------110 -------------------------------------------90----------------------------------200





Now, I found the first part!!

16/200=.08 or 8% probability of finding a home $100,000 or less.

(First part described)
16 is total of houses under $100,000/total number of houses 200

Second part

110/200=.55 or 55% probability of finding a home less then 2000 sq. feet

(2nd part described)
There are a total of 110 houses that are less then 2000 sq. feet. I took this number and divided by the total number of houses in the chart (200) and got my answer for this part.


THIS IS WHERE I NEED HELP!!!!!

Now that I have figured out the two answers independently of one another, I do not know how to write an answer or even go about finding the answer for the two sections combined. Again, the problem states

"What is probability of finding a home in the USA advertised on this website that is less than $100,000 or under 2000 sq. feet"?



Can you help??

tkhunny
05-01-2008, 09:12 AM
Add up all the pieces and don't count anything twice.

16 + 110 - 13 = 113

Or...

5+92+13+3 = 113