How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

10+10 and 11+11 can give you the same answer.

Explain how?

I look at you, you look at me, I raise my right, you raise your left. What am I?

If you toss a coin 10 times and it lands heads up every time, what are the chances it will land heads up if you toss it again?

There is a hypothetical state between the USA and Mexico border 'Tango'.
Here 70 percent of the population have defective eyesight, 75 percent are hard of hearing, 80 percent have Nose trouble and 85 percent suffer from allergies, what percentage (at a minimum) suffer from all four ailments?

Can you find out what is missing?

1 3 5
2 4 ?

Hint: It's not six. Think out of the box.

Can you count the number of seconds in a year?

Clue: You need to bother about calculation.

Here is a Swiss Cross. You have to make two straight cuts in the figure so that it is divided into four congruent pieces. Also, you should be able to join these pieces into a square then. Can you accept this challenge?

There are three boxes of different sizes with three cupcakes inside each of the boxes in Christina's kitchen. At night her daughter wakes up and goes to the kitchen. She opens a box and eats all three cakes.

But in the morning Christina finds out that each box still had three cupcakes. How?

You board a train. The train will have to enter a tunnel soon. You are claustrophobic. Which place is the best for you to sit?