**PROBLEM 1**

Among US Households, only 20% have a landline phone. A telemarketing campaign will involve a SRS of 2000 households. Let **X**be the **number**of households that have a landline phone among the 2000 households randomly chosen.

What is the mean of **X**?

What was the standard deviation of **X**?

Note: the correction factor can be ignored in this case

Assuming**X**is approximately normal, find P(**X**>300).

**PROBLEM 2**

A supplier of ballpoint pens guarantees a low defective rate. Sara receives a shipment of 500 pens (and unknown to Sara, but known to you, exactly 13 are defective). Sara decides to randomly check 100 pens. Let **X**be the **number**of defectives Sara finds among the 100 randomly selected pens.

The possible values of **X**are whole numbers ranging from _____ to _____.

What is the mean of **X**?

What was the standard deviation of **X**?

Hint: you need the correction factor

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