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प्रश्न
Three squares of chessboard are selected at random. The probability of getting 2 squares of one colour and other of a different colour is ______.
विकल्प
`16/21`
`8/21`
`3/32`
`3/8`
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उत्तर
Three squares of chessboard are selected at random. The probability of getting 2 squares of one colour and other of a different colour is `16/21`.
Explanation:
In a chessboard, there are 64 squares of which 32 are white and 32 are black.
Since 2 of one colour and 1 of other can be 2W, 1B, or 1W, 2B, the number of ways is (32C2 × 32C1) × 2 and also, the number of ways of choosing any 3 boxes is 64C3.
Hence, the required probability = `(""^32C_2 xx ""^32C_1 xx 2)/(""^64C_3)`
= `16/21`.
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| Assignment | ω1 | ω2 | ω3 | ω4 | ω5 | ω6 | ω7 |
| (a) | 0.1 | 0.01 | 0.05 | 0.03 | 0.01 | 0.2 | 0.6 |
| (b) | `1/7` | `1/7` | `1/7` | `1/7` | `1/7` | `1/7` | `1/7` |
| (c) | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 | 0.6 | 0.7 |
| (d) | –0.1 | 0.2 | 0.3 | 0.4 | -0.2 | 0.1 | 0.3 |
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| (iv) |
\[\frac{1}{14}\]
|
\[\frac{2}{14}\]
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\[\frac{3}{14}\]
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\[\frac{4}{14}\]
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\[\frac{5}{14}\]
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\[\frac{6}{14}\]
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\[\frac{15}{14}\]
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