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The average ages of three persons is 27 years. Their ages are in the proportion of ...

The average ages of three persons is 27 years. Their ages are in the proportion of 1:3:5.What is the age in years of the youngest one among them
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  • A 11
  • B 9
  • C 7
  • D 6
Correct Answer: Option B
Explanation:
To solve this problem, follow these steps:

1. Find the total sum of the ages:

The average age of the three persons is 27 years. Since there are three persons, the total sum of their ages is:

\[
\text{Total sum} = \text{Average} \times \text{Number of persons} = 27 \times 3 = 81
\]

2. Use the given ratio to find the individual ages:

The ages are in the ratio 1:3:5. Let the ages be \( x \), \( 3x \), and \( 5x \). The sum of these ages should equal the total sum we calculated:

\[
x + 3x + 5x = 81
\]

Simplify to find \( x \):

\[
9x = 81
\]
\[
x = \frac{81}{9} = 9
\]

3. Find the age of the youngest person:

The youngest person’s age is \( x \), which is:

\[
x = 9
\]

Thus, the age of the youngest person is 9 years, which corresponds to option B.

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