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

Why is it very easy to weigh a fish?

What is the Surname of Barbie Doll?

Can you convert the number zero(0) into a positive number using just one mathematical operator ?

Two friends were betting. One said to the other, "The coin will be flipped twenty times and each time the coin lands on the head, I will give you $2 and each time it lands on the tale, you will give me $3." After flipping the coin twenty times not a single penny was exchanged among them.

How many times did the coin land on heads?

You are mixing a mixture of cement and Sand with five gallons of water. You have a garden hose giving you all the water you need. The problem is that you only have a four-gallon bucket and a seven-gallon bucket and neither has graduation marks. Find a method to measure five gallons.

You Throw The Outside, Cook The Inside
Eat The Outside, Throw The Inside.

What Is It?

Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

Six people park their car in an underground parking of a store. The store has six floors in all. Each one of them goes to a different floor. Simon stays in the lift for the longest. Sia gets out before Peter but after Tracy. The first one to get out is Harold. Debra leaves after Tracy who gets out on the third floor.

Can you find out who leaves the lift on which floor?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?