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प्रश्न
In a medical examination of students of a class, the following blood groups are recorded:
| Blood group | A | AB | B | O |
| Number of students | 10 | 13 | 12 | 5 |
A student is selected at random from the class. The probability that he/she has blood group B, is:
विकल्प
`1/4`
`13/40`
`3/10`
`1/8`
उत्तर
`bb(3/10)`
Explanation:
Total number of students in a medical examination, n(S) = 40
Number of persons who have B blood group, n(E) = 12
∴ Probability that he/she has blood group B = `(n(E))/(n(S)) = 12/40 = 3/10`
Hence, the probability that he/she has blood group B is `3/10`.
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|
Monthly income (in Rs.) |
Vehicles per family | |||
| 0 | 1 | 2 | Above 2 | |
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| 13000 – 16000 | 2 | 469 | 59 | 25 |
| 16000 or more | 1 | 579 | 82 | 88 |
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(v) owning not more than 1 vehicle.
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