How many times can you subtract the number two from the number fifty?

Take one out and scratch my head, I am now black but once was red. What am I?

What is the fastest way to double your money?

Can you find out the smallest number that can be conveyed as the sum of three squares in three unique ways?

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

When monkey rotate the gear, which mark will be hit 1 or 2 ?

Find a 9-digit number, which you will gradually round off starting with units, then tenth, hundred etc., until you get to the last numeral, which you do not round off. The rounding alternates (up, down, up ...). After rounding off 8 times, the final number is 500000000. The original number is commensurable by 6 and 7, all the numbers from 1 to 9 are used, and after rounding four times the sum of the not-rounded numerals equals 24.

Replace the question mark with the number below given a simple math problem.

Count the number of triangles in the picture below:

In which direction should the missing arrow point?