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

You have $100 with you and you have to buy 100 balls with it. 100 is the exact figure and you can't go below or above the numbers and you have to use the entire $100. If there is no kind of tax applied how many of each of the following balls will you be able to buy:

Green Balls costing $6
Yellow Balls costing $3
Black Balls costing $0.10

Now, how many of each must you buy to fulfil the condition given?

What has a bottom at the top?

When I go in I might cause pain. I cause you to spit and ask you not to swallow. I can fill your hole. What am I?

In a contest, four fruits (an apple, a banana, an orange, and a pear) have been placed in four closed boxes (one fruit per box). People may guess which fruit is in which box. 123 people participate in the contest. When the boxes are opened, it turns out that 43 people have guessed none of the fruits correctly, 39 people have guessed one fruit correctly, and 31 people have guessed two fruits correctly.
How many people have guessed three fruits correctly, and how many people have guessed four fruits correctly

You see a mathematical expression in the picture. Can you think of a movie that this expression refers to?

What does below science rebus mean?

Ag Ag Ag
Ag SPOON Ag
Ag Ag Ag

A chicken farmer has figured out that a hen and a half can lay an egg and a half in a day and a half. How many hens does the farmer need to produce one dozen eggs in six days?

I have lakes with no water, mountains with no stone and cities with no buildings. What am I?

Solve the equation in the image by looking at the pattern closely.