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प्रश्न
A box contains 10 tickets, 2 of which carry a prize of ₹ 8 each. 5 of which carry a prize of ₹ 4 each and remaining 3 carry a prize of ₹ 2 each. If one ticket is drawn at random, find the mean value of the prize.
उत्तर
| X: | 8 | 8 | 4 | 4 | 4 | 4 | 4 | 2 | 2 | 2 |
| P(X): | `1/10` | `1/10` | `1/10` | `1/10` | `1/10` | `1/10` | `1/10` | `1/10` | `1/10` | `1/10` |
Probability of having one ticket out of 10 ticket = `1/10`
μ = ∑xip
= `8 xx 1/10 + 8 xx 1/10 + 4 xx 1/10 + 4 xx 1/10 + 4 xx 1/10 + 4 xx 1/10 + 4 xx 1/10 + 2 xx 1/10 + 2 xx 1/10 + 2 xx 1/10`
= `(16 + 20 + 6)/10`
= `42/10`
= 4.2
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