Marc was born on his grandmother's 56th birthday. In how many years will Marcs grandmother be 5 times as Marc will be then?

Therefore 70 year Marc's grandmother be 5 times of as Marc will be after (70-56) = 14 year.

Step-by-step explanation:

Given, Marc was born on his grandmother's 56th birthday.

Let, x year will Marc's grandmother be 5 times as Marc will be then.

At that time the age of Marc will be = (x-56) year

According to the problem,

x = 5 (x-56)

⇔x = 5x - 280

⇔x-5x = - 280

⇔-4x=-280

⇔x=70

Therefore 70 year Marc's grandmother be 5 times of as Marc will be after (70-56) = 14 year.