# Probability and Venn diagrams.

• Jun 1st 2010, 02:36 AM
acevipa
Probability and Venn diagrams.
A survey was carried out in a new development area to gain data on home-delivered newspapers. 110 homes were selected at random and the occupants asked whether they had the daily newspaper or the weekend home paper delievered. 74 received the daily paper, 58 received the weekend apper and 10 receieved no paper at all.

Determine the probability that the last home visited in this survey received both the daily and weekend papers.
• Jun 1st 2010, 04:18 AM
CaptainBlack
Quote:

Originally Posted by acevipa
A survey was carried out in a new development area to gain data on home-delivered newspapers. 110 homes were selected at random and the occupants asked whether they had the daily newspaper or the weekend home paper delievered. 74 received the daily paper, 58 received the weekend apper and 10 receieved no paper at all.

Determine the probability that the last home visited in this survey received both the daily and weekend papers.

You are required to work out how many of the 110 homes have both papers delivered, call this number N, then the required probability is N/110.

CB
• Jun 1st 2010, 04:58 AM
acevipa
Quote:

Originally Posted by CaptainBlack
You are required to work out how many of the 110 homes have both papers delivered, call this number N, then the required probability is N/110.

CB

Yes but how do you work that out?
• Jun 1st 2010, 05:18 AM
mr fantastic
Quote:

Originally Posted by acevipa
Yes but how do you work that out?

Draw a Venn diagram. Then, it should be clear that (74 - N) + N + (58 - N) = 100 ....