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 '13...... You will be glad to note that only Gaurav Agarwal could solve it.

Answer 1

as it's impossible to get an odd number by adding odd no.s odd no.of times,we can do this by using factorials..
eg: 1+3+3!+11+9 =30
      7+3+11+3+3!=30 and so on..
hope this helps.. :)

Answer 2

The sum of three odd numbers gives an odd number
So, the sum of 3 given odd numbers doesnt results 30
So, it is an impossible factor
here we can't use 3! too
because 3! [3×2×1] results a even number 6
so we cant use it.
If there will be an allowance of factorials, then the answers will be
3!+1+5+7+11=30
3!+1+3+7+13=30