How can you make the following equation true by drawing only one straight line: 5+5+5=550 ?

It's pretty hard to give up.
If you remove a part of it, you will be left with a bit.
Even if you remove another part, the bit still remains.
Remove one more and it still remains.

What is it?

What is next number in the pattern below:

131 517 192 123 ?

A research team went to a village somewhere between the jungles of Africa. Luckily for them, they reached the day when quite an interesting custom was to be performed. The custom was performed once a year as they confirmed and was performed in order to collect the taxes from every male of the region.

The taxes were to be paid in the form of grains. Everyone must pay pounds of grain equaling his respective age. This means a 20-year-old will have to pay 20 pounds of grain and a 30-year-old will pay 30 pounds of grain and so on.

The chief who collects the tax has 7 weights and a large 2-pan scale to weigh. But there is another custom that the chief can weigh only three of the seven weights.

Can you find out the weights of the seven weights? Also, what is the maximum age of the man that can be weighed for the payment of taxes?

What is the largest number you can write with just 3 digits?

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

When I got four, I have it none.
When I got two, I have it some.
When I got none, I have it all.

What is it?

In a chess board, the queen piece can move horizontally, vertically and diagonally freely. The picture represents the same.Can you place 8 queens on the board in a manner that none of the queens can attack each other?

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

How can you tell a raw egg from a hard-boiled egg?