It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

In a fruit store, there was a unique weighing machine that was made to weigh only cherries and strawberries as they were priced the same.

Other fruits like watermelons or mango had different machines as they were expensive.

A man successfully buys watermelons at the price of cherries. How?

Baseball bat and ball cost $100. If the bat cost $99 more than the ball, what is the cost of each?

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

Find out the missing number in the picture attached:

By including only four matchsticks in below picture, you have to make "Four Triangles And Two Squares"

What runs around the whole yard without moving?

An infinite number of mathematicians are standing behind a bar. The first asks the barman for half a pint of beer, the second for a quarter pint, the third an eighth, and so on. How many pints of beer will the barman need to fulfill all mathematicians' wishes?

Two boys were admitted to a school. When the headmaster asks them about their parents, they tell him that they have same parents (father and mother). On further inquiry, it turns out that they both share the same date for their birthday.

"Are you twins," ask the headmaster.
"No," replies the boys.

Is it possible?

A train leaves from point A for point B at 80 mph. After half an hour, another train leaves from point B for point A at 60 mph.

Which of the trains will be farther from point A when they meet ?