Question

Solve this..
◻ ➕ ◻ ➕ ◻=30

Fill the boxes using
(1, 3, 5, 7, 9, 11, 13, 15)

U can also repeat the numbers.

This question came in UPSC Final Exams held in Dec 2013.

You will be glad to note that only Gaurav Agarwal (IAS Topper) could solve it.

Answer 1

it is not possible to get an even number by adding an odd number but for this possible only if use factorials method
so
3! + 3! + 3! + 3! + 3! =30        [3! = 1*2*3 = 6]
6 + 6 + 6 + 6 + 6 = 30 

Answer 2

There can be many answers but the basic idea is using factorial. Factorial is the product of all the numbers from 1 to that number. For example 4! = 1 x 2 x 3 x 4 = 24.
 
So, 3! + 11 + 13  = 30
Similarly you can find many such answers.

Hope that helps !!