Question

На доске было написано арифметическое выражение, значение которого равнялось 2007. Вася поменял в этом выражении два знака действия местами, и значение выражения стало равным 2008. Покажите, как такое могло произойти.

Answer 1

2007.5-05+0
2007.5+0.5-0

Answer 2

2009-3+2^0=2007; 2009-2+3^0=2008

Answer 3

Answer in detail. On the board was written an arithmetic expression, the value of which was equal to 2007. Vasya changed two signs of action in this expression, and the value of the expression became equal to 2008. Show how this could happen.

An arithmetic expression is a combination of numbers and symbols that represent a mathematical calculation. For example, 3 + 5 is an arithmetic expression that means the sum of 3 and 5. Some other symbols that can be used in arithmetic expressions are - (subtraction), * (multiplication), / (division), and ^ (exponentiation).

To answer the question, we need to find an arithmetic expression that has the value of 2007, and then change two signs of action in it to get the value of 2008. One possible way to do this is as follows:

- Start with the expression 2000 + 10 * 2 - 3, which has the value of 2007. - Change the sign of + to - and the sign of - to +, so the expression becomes 2000 - 10 * 2 + 3. - Calculate the new value of the expression, which is 2008.

Therefore, one possible way that Vasya could change the value of the expression from 2007 to 2008 is by swapping the signs of + and - in the expression 2000 + 10 * 2 - 3.