Problems

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The graph of the function \(y=kx+b\) is shown on the diagram below. Compare \(|k|\) and \(|b|\).

Compare the numbers: \(A=2011\times 20122012\times 201320132013\) and \(B= 2013\times 20112011 \times 201220122012\).

A rectangle of size \(199\times991\) is drawn on squared paper. How many squares intersect the diagonal of the rectangle?

Suppose you have 127 1p coins. How can you distribute them among 7 coin pouches such that you can give out any amount from 1p to 127p without opening the coin pouches?

The board has the form of a cross, which is obtained if corner boxes of a square board of \(4 \times 4\) are erased. Is it possible to go around it with the help of the knight chess piece and return to the original cell, having visited all the cells exactly once?

Prove that: \[a_1 a_2 a_3 \cdots a_{n-1}a_n \times 10^3 \equiv a_{n-1} a_n \times 10^3 \pmod4,\] where \(n\) is a natural number and \(a_i\) for \(i=1,2,\ldots, n\) are the digits of some number.

In a room there are some chairs with 4 legs and some stools with 3 legs. When each chair and stool has one person sitting on it, then in the room there are a total of 39 legs. How many chairs and stools are there in the room?

You are given 10 different positive numbers. In which order should they be named \(a_1, a_2, \dots , a_{10}\) such that the sum \(a_1 +2a_2 +3a_3 +\dots +10a_{10}\) is at its maximum?