Answer:
26 years old
Step-by-step explanation:
We know that average/mean is calculated by dividing the sum of all values by the number of values.
So, if there are two people, we can work the equation backwards to find what the original values were.
(I will use x to represent dr frost's age)
[tex]\frac{x + 13}{2}[/tex] = 19.5
×2 ×2 (multiply both sides by 2)
x + 13 = 39
- 13 - 13 (subtract 13 from both sides)
x = 26
dr frost = 26 years old
To check, we can re-calculate the average. 26 + 13 = 39. 39 / 2 = 19.5
So, Dr. Frost is 26 years old.
