Spencer is 14 years older than his sister Kelly. Three years from now, he will be three times as old as Kelly. How old are they now?
To find out how old Spencer and Kelly are currently, we can set up an equation based on the given information.
Let's assume Kelly's current age is K.
According to the information given, Spencer is 14 years older than Kelly. So, Spencer's current age is K + 14.
Three years from now, Kelly's age will be K + 3, and Spencer's age will be (K + 14) + 3.
As per the given condition, three years from now, Spencer will be three times as old as Kelly. So, we can set up the equation:
(K + 14) + 3 = 3(K + 3)
Now, let's solve the equation:
K + 14 + 3 = 3K + 9
K + 17 = 3K + 9
17 - 9 = 3K - K
8 = 2K
K = 8 / 2
K = 4
Now that we have found Kelly's current age to be 4, we can find Spencer's current age by substituting it into the equation:
Spencer's current age = Kelly's current age + 14
Spencer's current age = 4 + 14
Spencer's current age = 18
Therefore, Kelly is currently 4 years old, and Spencer is currently 18 years old.
Now:
Kelly ---- x
Spencer ---- x+14
3 years from now:
Kelly = x+3
Spencer = x+14+3 = x+17
x+17 = 3(x+3)
solve for x, sub into my definitions