Can you find out the missing number in the grid?

In order to complete the racing competition, the Mexico racetrack has to submit its top and the most famous three horses to win the competition. Due to an electrical storm, all the records are cleared and no one knows which horse holds the record. They all look identical and it becomes even more difficult to differentiate the horses. There are 25 horses in the Mexico racetrack. But there can be only five horses at a time on the track. What will the least number of races that can be conducted to find out the three fastest horses?

Can you find the odd number in the following five choices?

1) 482636
2) 259807
3) 865195
4) 104739
5) 391744

If you had a pizza with crust thickness 'a' and radius 'z', what's the volume of the pizza?

You need to climb ten stairs. At every stair, you can either take one step up or you can jump two steps up.

In how many different ways you can climb 10 stairs?

What is always in front of you but can’t be seen?

Readers with high attention to detail can spot the mistake in the stack of shoes in 5 seconds. Are you one of them? Test your visual skills now!

Solve the equation by replacing the alphabet with numbers.

MOM + MOM + NO = BOOK=

Can you divide numbers from 1 to 9 (1 2 3 4 5 6 7 8 9) into two groups so that the sum of the numbers of each group is equal?

Note: 9 cannot be turned over to make it 6.

Take one out and scratch my head, I am now black but once was red. What am I?