Sally is four times lindas age. How old are sally and linda now if, in ten years time the sum of their ages will be 75?
So, what have they told you?
S = 4L
(S+10)+(L+10) = 75
Now just solve for S and L
Today:
Linda is X yrs. old.
Sally is 4x yrs. old.
Ten yrs. from today:
Linda will be x+10 yrs. old.
Sally will be 4x+10 yrs. old.
(x+10) + (4x+10) = 75.
X = ?
4x = ?
To solve this problem, we need to set up equations based on the given information and solve them simultaneously.
Let's define Sally's current age as "S" and Linda's current age as "L".
According to the first statement, "Sally is four times Linda's age", we can write the equation:
S = 4L (equation 1)
Next, consider the second statement, "In ten years, the sum of their ages will be 75." In ten years, Sally's age will be S + 10, and Linda's age will be L + 10. So, the equation becomes:
(S + 10) + (L + 10) = 75 (equation 2)
To simplify equation 2, we can remove the parentheses:
S + L + 20 = 75
Now, let's substitute the value of S from equation 1 into equation 2:
4L + L + 20 = 75
Combine like terms and simplify:
5L + 20 = 75
5L = 75 - 20
5L = 55
L = 55 / 5
L = 11
Now that we know Linda's age (L), we can substitute this value back into equation 1 to find Sally's age (S):
S = 4L
S = 4 * 11
S = 44
Therefore, Sally is 44 years old, and Linda is 11 years old.