The average age of three friends A, B, C is 20 years. The average age of A and B is 19 years. What is the age of C?

Options

A. A) 20 years
B. B) 21 years
C. C) 22 years
D. D) 24 years

Explanation

To find the age of friend C, we can follow these steps:

### Step 1: Calculate the total age of A, B, and C
The average age of A, B, and C is given as 20 years. Since there are three friends, we can calculate their total age by multiplying the average age by the number of friends:
\[ \text{Total age of A, B, and C} = \text{Average age} \times \text{Number of friends} = 20 \times 3 = 60 \text{ years} \]

### Step 2: Calculate the total age of A and B
The average age of A and B is given as 19 years. Since there are two friends, we can calculate their total age:
\[ \text{Total age of A and B} = \text{Average age} \times \text{Number of friends} = 19 \times 2 = 38 \text{ years} \]

### Step 3: Calculate the age of C
Now, we can find the age of C by subtracting the total age of A and B from the total age of A, B, and C:
\[ \text{Age of C} = \text{Total age of A, B, and C} - \text{Total age of A and B} = 60 - 38 = 22 \text{ years} \]

### Final Answer
The age of C is 22 years.

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