Problems

Age
Difficulty
Found: 1176

A young mathematician felt very sad and lonely during New Year’s Eve. The main reason for his sadness (have you guessed already?) was the lack of mathematical problems. So he decided to create a new one on his own. He wrote the following words on a small piece of paper: “Find the smallest natural number \(n\) such that \(n!\) is divisible by 2018”, but unfortunately he immediately forgot the answer. What is the correct answer to this question?

Find such a natural number \(n\) that all the numbers \(n+1\), \(n+2\), ..., \(n+2018\) are composite.

The numbers \(2^{2018}\) and \(5^{2018}\) are expanded and their digits are written out consecutively on one page. How many digits are on the page?

Is it possible for \(n!\) to be written as \(2015000\dots 000\), where the number of 0’s at the end can be arbitrary?

A battle of the captains was held at a maths battle. The task was to write the smallest number such that it is divisible by 45 and consists of only 1’s and 0’s as digits. What do you think was the correct answer?

It is known that a natural number is three times bigger than the sum of its digits. Is it divisible by 27?

A number was left written on the white board after a maths class. The number consisted of one hundred 0’s, one hundred 1’s, and one hundred 2’s as digits. A cleaner was about to wipe it off when suddenly he saw a small comment written in a corner. The comment stated that the number was a square number. He fetched a sigh and wrote “it not a square number”. Why was he right?

A stoneboard was found on the territory of the ancient Greek Academia as a result of archaeological excavations.

The archeologists decided that this stoneboard belonged to a mathematician who lived in the 7th century BC. The list of unsolved problems was written on the stoneboard. The archaeologists became thrilled to solve the problems but got stuck on the fifth. They were looking for a 10-digit number. The number should consist of only different digits. Moreover, if you cross any 6 digits, the remaining number should be composite. Can you help the archeologists to figure out the answer?

Divide 15 walnuts into four groups, each group consisting of a different whole number of nuts.