What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

Different lights make me strange by changing me into different sizes. What am I?

Find the combined weight of the Cat, Dog and Rabbit in the given picture.

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?

You need to arrange three 7 and mathematical symbols to form number 1?

10 people came into a hotel with 9 rooms and each guest wanted his own room. The bellboy solved this problem.
He asked the tenth guest to wait for a little with the first guest in room number 1. So in the first room, there were two people. The bellboy took the third guest to room number 2, the fourth to number 3, ..., and the ninth guest to room number 8. Then he returned to room number 1 and took the tenth guest to room number 9, still vacant.
How can everybody have his own room?

What's the best place to go shopping in the ocean?

What is the four-digit number in which the first digit is one-third the second, the third is the sum of the first two, and the last is three times the second?

Can you find the next number in the below sequence
3 , 7 , 10 , 11 , 12 , 17 ?

Count the Triangle in the figure given below: