Question

explain answer please

Answer 1

After putting 4 balls into each box, there are 2 left.
Then, you have to put the ball in atleast one box. Then here this box has 5 balls. Then you can put the other in this box or in any other box.
So here at least one box should have atleast five balls.
Hope that will help. Thanks.

Answer 2

Hello Friend !

This is explained below. Please see to it :-

Total balls are 18

Total number of boxes are 4 

In order to satisfy the condition that no box is empty, balls are filled symmetrically in all the boxes.

Now, balls in each bag is 4 ( i.e., 4 in each , ∴ 16 in total )

After 16 balls are filled symmetrically in the boxes, the condition is satisfied , but 2 balls are still left.

Therefore we can fill the remaining 1 ball in any one of the boxes and the 2 ball in any other box.

Therefore, at least one bag will have 5 balls.

Hope this helps !!!