Question

In Exercises 13–20, express the indicated degree of likelihood as a probability value between 0 and 1.

Randomness When using a computer to randomly generate the last digit of a phone number to be called for a survey, there is 1 chance in 10 that the last digit is zero

Short answer

The probability that the digit of a phone number is chosen to be 0 is 0.1.

Step-by-step solution

Given information

The last digit of a phone number is randomly generated from 0 to 9.

Define probability

Probability is the measure of how likely an event is to happen.

Its formula is

$P\left(A\right)=\frac{\text{Number}\text{of}\text{outcomes}\text{in}\text{favour}\text{of}A}{\text{Total}\text{number}\text{of}\text{outcomes}}$

The value of probability lies between 0 and 1 (inclusive).

Calculate the probability 

There is a 1 in 10 chance that the last digit is 0. It meansthere is one favorable digit (0) for the event from 10 choices (0 through 9).

The total number of digits from 0 to 9 is 10.

The number of zeros in this range is 1.

The probability of getting a zero is

$$\begin{gathered} P\left(\text{Getting}\text{a}\text{zero}\right)=\frac{1}{10} \\ =0.1 \end{gathered}$$

Therefore, the probability of getting a zero in the random generation of digits is 0.1.