Look at your answer. If Sean's brother is 12 now, how could he have been 5 years old five years ago?
Sean's age years ago:
Sean's brother's age years ago:
Sean's age years ago was 3 times as old as Sean's brother's age years ago.
In equations:
Sean is 20 and his brother is 12. How many years ago was Sean three times as old as his brother?
MY WORK:
20 - x = 3(x)
20 - x = 3x
20 = x + 3x
20 = 4x
20/4 = x
5 = x
Sean's current age is 20.
Sean's age some years ago is 20 - x.
I just found x to be 5.
So, 20 - 5 = 15.
15 is three times more than 5.
So, when Sean was 15 years old, his brother was 5.
Is this correct?