5 years ago, the age of a man was 7 times the age of his son. The age of the man will be 3 times the age of his son in five years from now. How old is the man now?

Given:

5 years ago, Man's age = 7 × Son's age

5 years from now, Man's age = 3 × Son's age

Calculations:

Let the current age of the man be M and the current age of the son be S.

According to the first condition (5 years ago):

M - 5 = 7(S - 5)

⇒ M - 5 = 7S - 35

⇒ M = 7S - 30 (Equation 1)

According to the second condition (5 years from now):

M + 5 = 3(S + 5)

⇒ M + 5 = 3S + 15

⇒ M = 3S + 10 (Equation 2)

Now, equate Equation 1 and Equation 2:

7S - 30 = 3S + 10

⇒ 7S - 3S = 10 + 30

⇒ 4S = 40

⇒ S = 10

Substitute the value of S into Equation 2 to find M:

M = 3(10) + 10

⇒ M = 30 + 10 = 40

∴ The man is currently 40 years old.