## Rajshahi Higher Secondary 2017 P4

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samiul_samin
Posts: 1007
Joined: Sat Dec 09, 2017 1:32 pm

### Rajshahi Higher Secondary 2017 P4

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?

SA'AD
Posts: 5
Joined: Wed Jan 16, 2019 10:17 pm

### Re: Rajshahi Higher Secondary 2017 P4

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..