Question
Right now Seth's age is the age of his brother Eric. Twenty-one years ago, Eric was twice as old as Seth. What are their ages now?
Answers
GPT 3.5
Let's assume Seth's current age is x and Eric's current age is y.
According to the given information, Seth's age right now is the age of his brother Eric. Therefore, x = y.
Twenty-one years ago, Seth's age would have been x - 21 and Eric's age would have been y - 21.
According to the second piece of information given, Eric was twice as old as Seth twenty-one years ago. Therefore, we can write the equation: y - 21 = 2(x - 21).
Since x = y, we can substitute x for y in the equation: x - 21 = 2(x - 21).
Expanding the equation, we get x - 21 = 2x - 42.
Rearranging the equation, we have 2x - x = 42 - 21.
Simplifying, we get x = 21.
Therefore, Seth's current age (x) is 21 years old.
Since x = y, Eric's current age is also 21 years old.
So, Seth and Eric are both 21 years old now.
According to the given information, Seth's age right now is the age of his brother Eric. Therefore, x = y.
Twenty-one years ago, Seth's age would have been x - 21 and Eric's age would have been y - 21.
According to the second piece of information given, Eric was twice as old as Seth twenty-one years ago. Therefore, we can write the equation: y - 21 = 2(x - 21).
Since x = y, we can substitute x for y in the equation: x - 21 = 2(x - 21).
Expanding the equation, we get x - 21 = 2x - 42.
Rearranging the equation, we have 2x - x = 42 - 21.
Simplifying, we get x = 21.
Therefore, Seth's current age (x) is 21 years old.
Since x = y, Eric's current age is also 21 years old.
So, Seth and Eric are both 21 years old now.