Please can some one solve this probabilty question for me?

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low rainfall area, the occurence of rain in a city on a particular day is dependnt on whether it rained on previous or not. If it has rained on previous, the probability distribution for rain the next day is...

Event Probability
No rain 0.50
1 cm 0.25
2cm 0.15
3cm 0.05
4cm 0.03
5cm 0.02

If it didnt rain the previous day the probability distribution is as follows
No rain 0.75
1cm 0.15
2cm 0.06
3cm 0.04

Simulate the city`s rain in the next 15 days and find out the total number of days without rainfall and also the total rainfall during these 15 days. It may be assumed that the day before it didnt rain.
You may use the following random numbers.
67,63,39,55,29,78,70,06,78,76,25,48,93,62,84.

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by vineeshp » Wed Apr 20, 2011 7:02 am
Sorry, no answer here.

What are the random numbers for? This doesn't look like a Gmat qn.
Vineesh,
Just telling you what I know and think. I am not the expert. :)

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by jaymw » Wed Apr 20, 2011 8:00 am
low rainfall area, the occurence of rain in a city on a particular day is dependnt on whether it rained on previous or not. If it has rained on previous, the probability distribution for rain the next day is...

Event Probability
No rain 0.50
1 cm 0.25
2cm 0.15
3cm 0.05
4cm 0.03
5cm 0.02

If it didnt rain the previous day the probability distribution is as follows
No rain 0.75
1cm 0.15
2cm 0.06
3cm 0.04

Simulate the city`s rain in the next 15 days and find out the total number of days without rainfall and also the total rainfall during these 15 days. It may be assumed that the day before it didnt rain.
You may use the following random numbers.
67,63,39,55,29,78,70,06,78,76,25,48,93,62,84.
I agree that this really does not have anything to do with GMAT. Granted, there are some few probability questions on the GMAT, but those can be solved in 2 minutes. This one, however, will take significantly longer and from the looks of it I'd say it was taken from a statistics book that was by no means written for the GMAT. Studying with those kinds of questions will much rather hinder than help you!

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by Stuart@KaplanGMAT » Wed Apr 20, 2011 10:42 am
Hi,

as others have noted, this is not even remotely similar to a GMAT question. While it's an interesting statistics problem, people studying for the GMAT can safely ignore it.
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