How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

A rubber ball keeps on bouncing back to 2/3 of the height from which it is dropped. Can you calculate the fraction of its original height that the ball will bounce after it is dropped and it has bounced four times without any hindrance ?

How can I get the answer 24 by only using the numbers 8,8,3,3?

You can use the main signs add, subtract multiply and divide.

Can you find out the smallest number that can be conveyed as the sum of three squares in three unique ways?

Can you find out the remainder when 3^300 is divided by 5?

Find three whole, positive numbers that have the same answer when multiplied together as when added together.

Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

There are two candles. Both will only burn exactly for an hour. How will you use these two candles to measure forty-five minutes?

Use the digits from 1 up to 9 and make 100.

Follow the rules.
=> Each digit should be used only once.
=> You can only use addition.
=> For making a number, two single digits can be combined (for example, 4 and 2 can be combined to form 42 or 24)
=> A fraction can also be made by combining the two single digits (for example, 4 and 2 can be combined to form 4/2 or 2/4)

Question: how can we do this?

A Shopkeeper collects 71 rupees in the form of 20 paisa and 25 paisa.
He collects a total of 324 coins.

Can you tell me how many number of 20-paisa and 25-paisa he got?