I have eight fingers and two thumbs but I do not live. What Am I?

What always comes into a house through the keyhole?

13 decks of cards have been mixed. What is the minimum number of cards that must be taken out from the above-mixed cards to guarantee at least one 'four of a kind?

Can you find the least possible number such that

If the number is divided by 3, it gives the remainder of 1;
If the number is divided by 4, it gives the remainder of 2;
If the number is divided by 5, it gives the remainder of 3;
If the number is divided by 6, it gives the remainder of 4.

If you drop me I’m sure to crack, but give me a smile and I’ll always smile back. What am I?

What can go through glass without breaking it?

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?

I am beautiful, up in the sky. I am magical, yet I cannot fly. To people I bring luck, and to some people, riches. The boy at my end does whatever he wishes. What am I?

Find out the missing number in the picture attached:

You are mixing a mixture of cement and Sand with five gallons of water. You have a garden hose giving you all the water you need. The problem is that you only have a four-gallon bucket and a seven-gallon bucket and neither has graduation marks. Find a method to measure five gallons.