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**Choose the most appropriate option:**

12 defective pens are accidentally mixed with 132 good ones. It is not possible to just look at a pen and tell whether or not it is defective. One pen is taken out at random from this lot. Determine the probability that the pen taken out is a good one.

#### Options

`11/12`

`10/12`

`7/12`

`9/12`

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#### Solution

**`11/12`**

**Explanation:**

Number of good pens = 132

Number of defective pen = 12

∴ Total pens = 132 + 12 = 144

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