I want to fill my bucket using both cold and hot water.
I have two taps for both cold and hot water. The hot water tap fills the bucket in exact 6 hours and the cold water tap fills the bucket in exact 4 hours.
I turn both of them simultaneously but I forgot to turn off another tap which removes the water out of the bucket. This tap can empty the bucket in 12 hours.

How Long will it take to fill the bucket?

How many triangles are there on the puzzle below?

A mules travels the same distance daily.
I noticed that two of his legs travels 10km and the remaining two travels 12km.
Obviously two mules legs cannot be a 2km ahead of the other 2.

The mules is perfectly normal. So how come this be true ?

Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

A 3 digit number is such that it's unit digit is equal to the product of the other two digits which are prime. Also, the difference between it's reverse and itself is 396.

What is the sum of the three digits?

A rubber ball keeps on bouncing back to 2/3 of the height from which it is dropped. Can you calculate the fraction of its original height that the ball will bounce after it is dropped and it has bounced four times without any hindrance ?

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

Baseball bat and ball cost $100. If the bat cost $99 more than the ball, what is the cost of each?

Find the value of "?" in the ball picture Riddle below:

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211