Answer:
The present age of Mark is 25 years.
And present age of Lindsay is 20 years.
Step-by-step explanation:
Let us assume:
The present age of Lindsay = l
The present age of Mark = m
⇒ Age of Lindsay seven years ago = (l -7) years
and Age of Mark seven years ago = (m -7) years
According to question:
Lindsay is 5 years younger than Mark ⇒ l = m - 5
Seven years ago, the sum of their ages was 31 ⇒ (l-7) + (m -7) = 31
So, the given set of equation are:
l = m - 5 ......... (1)
(l-7) + (m -7) = 31
⇒ ((m - 5) -7) + (m -7) = 32 (from (1)
or, m -12 + m - 7 = 31
or, 2m = 31 + 19 = 50
⇒ m = 50 / 2 = 25, or m = 25
Hence,the present age of Mark = 25 years
So,the present age of Lindsay = 25 - 5 = 20 years
