Which flower has two lips?

What is full of holes but still holds water?

What has hands, but can’t clap?

Why are televisions attracted to people?

I have Rs.50 and I spend it in the way as below.

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

Use only one mathematical symbol and all numbers (0-9) to get a sum of 99

What goes up but never comes down?

A large water tank has two inlet pipes (a large one and a small one) and one outlet pipe. It takes 3 hours to fill the tank with the large inlet pipe. On the other hand, it takes 6 hours to fill the tank with the small inlet pipe. The outlet pipe allows the full tank to be emptied in 9 hours.

What fraction of the tank (initially empty) will be filled in 0.64 hours if all three pipes are in operation? Give your answer to two decimal places (e.g., 0.25, 0.5, or 0.75).

Why do we preferably have round manhole covers and not square ones?