The sum of the present ages of Aditi, Aditya and Aadya is 120 years. What was the sum of their ages 3 years ago?
111
\(111\) is correct.
When every person in a group gets older or younger by the same number of years, the total age of the group changes by that number multiplied by the number of people.
Each of the three people was 3 years younger three years ago, so the combined age falls by 3 years for every person.
Total reduction \(= 3 \times 3 = 9\) years.
Sum of ages 3 years ago \(= 120 - 9 = 111\) years.