Amelia calls people at random to conduct a survey. So far, 20 calls have been answered and 30 calls have not been answered. What is the approximate probability that someone answers the next call she makes?

A. [tex]$\frac{2}{3}$[/tex]
B. 0.6
C. [tex]$67\%$[/tex]
D. [tex]$40\%$[/tex]



Answer :

To determine the approximate probability that someone answers the next call Amelia makes, we need to follow a series of steps:

1. Calculate the total number of calls made:
Amelia has made a total of both answered and unanswered calls. Specifically, she has made:
[tex]\[ 20 \, (\text{calls answered}) + 30 \, (\text{calls not answered}) = 50 \, (\text{total calls}) \][/tex]

2. Find the probability of the next call being answered:
The probability that the next call will be answered is the ratio of the number of answered calls to the total number of calls made. Hence:
[tex]\[ \text{Probability} = \frac{\text{Number of answered calls}}{\text{Total number of calls}} = \frac{20}{50} \][/tex]

3. Simplify the fraction:
Simplifying [tex]\(\frac{20}{50}\)[/tex]:
[tex]\[ \frac{20}{50} = \frac{2}{5} \][/tex]

4. Convert the fraction to a percentage or decimal for comparison with the given options:
To compare with the given options:
[tex]\[ \frac{2}{5} = 0.4 = 40\% \][/tex]

Given the options:
- A. [tex]\(\frac{2}{3}\)[/tex]
- B. 0.6
- C. 67\%
- D. 40\%

The correct answer, matching the simplified fraction is:
[tex]\[ \text{D. } 40\% \][/tex]