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

If one and a half boys, eat one and a half burgers in one and a half hours.

How many burgers can 9 boys eat in 3 hours?

It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

The barber of Town shaves all men living in the town. No man living in the town is allowed to shave himself. The barber lives in that town. Who then shaves the barber of the town?

Twenty frogs are sitting on a log floating on the surface of a river. Two of them decide to jump off into the water.

How many frogs are there on the log at this moment?

Replace the 'X' with any mathematical symbol to make the expression equal to 111.

18 X 12 X 2 X 3 = 111

You have to put a letter on the following to make it a meaningful word. The only challenge is that you can't use 'E'.

S E Q U E N C _

Can you place three balls such that the equation shown in the picture holds true?

If it took eight men ten hours to build a wall, how long would it take four men to build it?

What number do you get when you multiply all of the numbers on a telephone's number pad?