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secondary 4 | E Maths
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Hi, may I know why is 0.7 rejected? I was wondering if we could see these events as dependent events since people are selected without replacement, so 1-(55/100*54/99)=0.7
Kindly advise, thank you so much :)
Date Posted: 2 years ago
Views: 398
You cannnot assume that the city has only 100 people.
Let's say the city has 1000 people.
The probability would be :
1 - (550/1000 × 549/999) ≈ 0.6977
If the city had 10000 people then the probability would be :
1 - (5500/10000 × 5499/9999) ≈ 0.69752
As you increase the number of people in the city, the probability will tend towards 0.6975
Which is equal to 1 - 0.55 × 0.55
Let's say the city has 1000 people.
The probability would be :
1 - (550/1000 × 549/999) ≈ 0.6977
If the city had 10000 people then the probability would be :
1 - (5500/10000 × 5499/9999) ≈ 0.69752
As you increase the number of people in the city, the probability will tend towards 0.6975
Which is equal to 1 - 0.55 × 0.55
Thank you so much Mr J :)
Wow! I've learnt something new from you. Awesome explanation, I understand now.
Thanks again and I hope you have a good evening.
Wow! I've learnt something new from you. Awesome explanation, I understand now.
Thanks again and I hope you have a good evening.
Welcome.
This question mainly deals with the extremes, i.e the limit when population goes to infinity.
This question mainly deals with the extremes, i.e the limit when population goes to infinity.
oh I see...:)
Noted with thanks, Mr J.
Noted with thanks, Mr J.
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Thanks Mr Yong.
Hi Candice, when you use 55/100 and 54/99 you are assuming that there are only 100 people in the population. In fact the population size is taken as so large that the p = .55 can be taken as constant.
Notes with thanks, Mr Yong.
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