Thread: secetary periodically checks, check answer please

A secretary periodically checks to see how many of the three lines into the office are busy. Her findings for one week were the following.

No. lines busy Frequency
0 20
1 65
2 25
3 10

Let the random variable X be the number of lines busy. Find the probability distribution of X.

My answer is.

X P(X)

0 0.20
1 0.65
2 0.25
3 0.10

Thanks for checking my answer.

Originally Posted by kwtolley

A secretary periodically checks to see how many of the three lines into the office are busy. Her findings for one week were the following.

No. lines busy Frequency
0 20
1 65
2 25
3 10

Let the random variable X be the number of lines busy. Find the probability distribution of X.

My answer is.

X P(X)

0 0.20
1 0.65
2 0.25
3 0.10

Thanks for checking my answer.

She checked 120 times, so the relative frequencies (which are our estimate
of the probabilities) are 20/120, 65/120, .. and so on.

RonL

thank you for checking, I wanted to make sure what I did was right.