The sum of a mother, her baby and her dog's weight is 170 Kg. How much does the baby weigh if the mother weighs 100 kg more than the combined weight of the baby and the dog, and the dog weighs 60 per cent less than the baby?

Move three sticks of the spiral below to form a square.

You measure my life in hours
I serve you by expiring
I vanish faster when I am thin
and slower when I am thick
The wind is my energy
What am I?

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

I’m tall when I’m young, and I’m short when I’m old. What am I?

Count the number of lines in the image below ?

Four cars come to a four-way stop, each coming from a different direction. They can’t decide who got there first, so they all go forward at the same time. All 4 cars go, but none crash into each other. How is this possible?

You need to remove two matchsticks to make the below equation true. Can you do it ?

What has one eye, but can’t see?

What work can one never finish?