Rajshahi Higher Secondary 2017 P4

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samiul_samin
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Joined: Sat Dec 09, 2017 1:32 pm

Rajshahi Higher Secondary 2017 P4

Unread post by samiul_samin » Mon Feb 18, 2019 7:44 pm

Your city has $2$ types of people: Statistics show that the people with private cars are responsible for traffic jam in $40%$ of cases, whereas other people are responsible in only $20%$ of cases. Imagine in your city $40%$ people have private car. Now if one person in responsible for traffic jam then what is the probability of having a private car?

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SA'AD
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Re: Rajshahi Higher Secondary 2017 P4

Unread post by SA'AD » Wed Apr 10, 2019 10:55 am

In case of 60 persons causing traffic jams, people with private cars that cause this are 40 in number.
In case of 1 person causing traffic jam, people with private cars that cause this are 40/60 in number.
=2/3 no. of people.
So the probability must be= 2/(3*40) =1/60 [ANS]
Be a good person but don't waste time to prove it..

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