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प्रश्न
A die has two faces each with number ‘1’, three faces each with number ‘2’ and one face with number ‘3’. If die is rolled once, determine
- P(2)
- P(1 or 3)
- P(not 3)
उत्तर
Total possible outcomes on a dice = 6
i. 2 is marked on 3 faces
There are 3 ways to get 2
P(2) = `3/6 = 1/2`
ii. 1 is on two faces.
∴ Ways to get 1, P(1) = `2/6`
3 is marked on one face. So 3 can be got in one way, P(3) = `1/6`
∴ P(1 or 3) = `2/6 + 1/6 = 3/6 = 1/2`
iii. 3 is on only one face out of 6 faces.
So ways of not getting 3 = 6 – 1 = 5
∴ P(not 3) =`5/6`
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