To solve this problem, let's break it down step-by-step:
1. Determine the number of telephones in Adelaide:
We know that there are 48,000 telephones.
2. Identify the ratio of telephones to the population:
It is given that there are 12.8 telephones per 100 people.
3. Calculate the total population:
To find the total population, we need to determine how many sets of 100 people there are for 48,000 telephones. We can set up the following equation based on the given ratio:
[tex]\[
\text{Population} = \left(\frac{\text{Number of Telephones}}{\text{Telephones per 100 people}}\right) \times 100
\][/tex]
Substituting the values:
[tex]\[
\text{Population} = \left(\frac{48,000}{12.8}\right) \times 100
\][/tex]
4. Calculate the exact population:
Dividing 48,000 by 12.8:
[tex]\[
\frac{48,000}{12.8} = 3750
\][/tex]
Now, multiplying by 100:
[tex]\[
3750 \times 100 = 375,000
\][/tex]
5. Round the population to the nearest thousand:
The exact population is 375,000. Since it is already a whole number in thousands, rounding it gives:
[tex]\[
\text{Population (rounded to the nearest thousand)} = 375,000
\][/tex]
By following these steps, we find that the population of Adelaide, rounded to the nearest thousand, is 375,000. Thus, the correct answer is:
(B) 375,000
