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**Choose the correct option from the given alternative:**

If the a d.r.v. X has the following probability distribution:

X | 1 | 2 | 3 | 4 | 5 | 6 | 7 |

P(X=x) | k | 2k | 2k | 3k | k2 | 2k2 | 7k2+k |

k =

#### Options

`1/7`

`1/8`

`1/9`

`1/10`

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#### Solution

If the a d.r.v. X has the following probability distribution:

X | 1 | 2 | 3 | 4 | 5 | 6 | 7 |

P(X=x) | k | 2k | 2k | 3k | k2 | 2k2 | 7k2+k |

k = `1/10`

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