You are presented with three boxes. One of them has a red ball inside and the other two have a black ball inside each of them. You are asked to pick up the one with red ball and you pick one. Now, one of the other boxes is opened and it is found to have a black ball.

You are presented with a chance to change your box with the one that is left closed. Will you change your box? Why or why not?

Make the seating arrangement of 10 children in such a way that there are 5 rows with 4 children in each row.

John was a very careless driver, so his owner Jacob gave him an offer that he will get an incentive of Rs.30 for every bottle box he delivered without breaking it and he will be charged Rs.90 for every bottle box he broke. Jacob gave John 100 bottles-box to deliver. After delivery, Jacob paid John Rs.2400. How many bottles-box did John break?

A word I know,
Six letters contain,
Subtract just one,
And twelve is what remains.

What number comes next in the series?

5 15 5 18 5 24 14 20 _

Decode below rebus
D
N
A
T
S , D

Three brothers Jacob, John, and James live in Mexico City. The product of the ages of these brothers is 175. Jacob and John are twins. How old is James?

How many times can you subtract the number 5 from 25?

What has many teeth, but cannot bite?

What goes up but never comes down?