Question

If the average of 13, 15, and a is 16. Then a is

• A. 4
• B. 20
• C. 18
• D. 16

Answer 1

Answer:

B. 20

The value of $a$ is 20.

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1. Write the average formula:
   $\text{Average} = \frac{\text{Sum of all numbers}}{\text{Total count of numbers}}$

2. Substitute the given values:
   $\frac{13 + 15 + a}{3} = 16$

3. Multiply both sides by 3 to eliminate the fraction:
   $13 + 15 + a = 16 \times 3$
   $28 + a = 48$

4. Subtract 28 from both sides to find $a$:
   $a = 48 - 28$
   $\mathbf{a = 20}$