what are integers? Integers are positive and negative numbers including zero.
Mia is going to visit a museum with her friends. Including herself, there are 9 people visiting the museum. Mia’s mother has given her 5 pomegranates to eat. However, discovering that she is short of 4 pomegranates she borrows them from their grocer. Now, Mia’s mother has to return 4 pomegranates to her grocer but she herself is left with zero pomegranates. So, if she gets 6 pomegranates she will have to return 4 to her grocer. The grocer writes 4 pomegranates as due. But how will he know whether he has to give 4 pomegranates or take them?
For these things we need and use integers. Now in Mia’s case, her grocer will write ‘ +4’ as he has to get 4 pomegranates from Mia’s mother. Why did he give ~ez_lsquo+ez_rsquo~ sign before number 4? This is because he owes Mia’s mother 4 pomegranates and will get them next she visits. Had Mia’s mother owed him 4 pomegranates, he would have written ‘– 4’.
How did we end up in ~ez_lsquo+ez_rsquo~ and ‘ – ‘ business? The concept of denoting ~ez_lsquo+ez_rsquo~ and ‘ - ‘before the number is what integers is about. The basic of integers lies in denoting correct sign before the product number after performing mathematical function between the two numbers.
Let’s take another example to clear the basic concept of denoting respective signs before the numbers.
Mr. James is a fruit seller. He sold 6 apples at a profit of $5, and sold oranges at a loss of $1.55. Later, at night he looks into his books and sees that he has written ‘+5’ which denotes profit of $5 and ‘-1.55’ that denotes loss.
Practice exercise on what are Integers
1. Amelia has 3 pencils, she asks Alice to give her 2 more. What sign will ‘2’ have for Amelia?
2. Amanda has 12 boxes; she gives Jean 5 boxes. What sign will 5 have for Jean?
3. John has 8 apples, he asks Sid to give him 2 more. What sign will 2 have for Sid?
4. Ross has 56 cards, he asks Rachel to lend him 13 more. What sign will 13 have for Rachel?
5. Emily has 3 chalks, she gives 1 to Nancy. What sign will 1 have for Nancy?
6. Joe has 19 books, he asks Monica to lend him 1 book. What sign will 1 have for Joe?
7. Lilian has 3 chocolates, she asks Amber to take 2 from her. What sign will 2 have for Amber?