what does the below math rebus puzzle mean?

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

If in a car race, the man who came two places in front of the last man finished one ahead of the man who came fifth, how many contestants were there?

If you paint a brown house white it will become a white house. If the stoplight changes from red to green, then the light is green. So, if you throw a white shirt into the Red Sea, what will it become?

Can you discover the missing number in this series?

37, 10, 82
29, 11, 47
96, 15, 87
42, ?, 15

Can you count the number of blocks in the picture below?

What is wrong in the below Picture?

What makes this number unique: 8,549,176,320?

What's a single-digit number with no value?

There is a square piece of paper with a hole that is denoted by the circle on the top right side in the given picture. You have to cut the paper in a manner that it forms two and only two separate pieces of paper and then rearrange the pieces in a manner that the holes come in the centre of the paper.