Probability

[lue]

An accident has occurred on a busy highway between cities A (with a population of 100000) and B
(with a population of 200000). It is known only that the victim has surname Smith and is from one of
the two cities. Records show that 1% of the city A population and 0.08% of the city B population
have the surname Smith. What is the probability that the victim is from city A?

 

[mmm4444bot]

Hello. What do you already understand about this exercise? Where did you get stuck? Please share your beginning efforts. Thank you.

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[lue]

i calculated the number of Smiths from each population,then I got stuck. I was confused from the get go but I did try. Hope you can help me

 

[Dr.Peterson]

i calculated the number of Smiths from each population,then I got stuck. I was confused from the get go but I did try. Hope you can help me

Please do as we ask and show details. We need to see what you did and where you got stuck, in order to help you just where you need it, using what you already know.

What numbers did you get? What did you try next?

 

[lue]

Please do as we ask and show details. We need to see what you did and where you got stuck, in order to help you just where you need it, using what you already know.

What numbers did you get? What did you try next?

Im so sorry. I said, City A = 1% divided by 100 X 100 000=1000
City B= 0,08% DIVIDED BY 100 X 200 000=160 .
Then I didnt know what to do. I tried adding 1000+160=1160 , then I said P{city A }= 1000/1160=0,862

 

[Dr.Peterson]

Im so sorry. I said, City A = 1% divided by 100 X 100 000=1000
City B= 0,08% DIVIDED BY 100 X 200 000=160 .
Then I didnt know what to do. I tried adding 1000+160=1160 , then I said P{city A }= 1000/1160=0,862

Sounds good! What part are you unsure of?

The one thing I'd do differently is the way you state the percentages. 1% IS 1/100, so you don't want to divide it by 100; you're dividing 1, not 1%, by 100. But that's just a detail. What you did is right.

 

[lue]

Sounds good! What part are you unsure of?

The one thing I'd do differently is the way you state the percentages. 1% IS 1/100, so you don't want to divide it by 100; you're dividing 1, not 1%, by 100. But that's just a detail. What you did is right.

I wasnt sure about it all. Thank you very much , I appreciate it.