# Integers – Multiplication of Integers.

**CBSE CLASS 7 MATHEMATICS**

**INTEGERS – Chapter 1**

**Multiplication of Integers:**

**I. Multiplication of a positive and a negative Integer:**

While multiplying a positive integer and a negative integer, we multiply them as whole numbers and put a minus sign (-) before the product. We thus get a negative integer.

Examples:

1. 4 x (-8) = -32

2. (-5) x 3 = -15

3. 9 x (-2) = -18

**II. Multiplication of two Negative Integers:**

We multiply the two negative integers as whole numbers and put the positive sign before the product. We can say that the product of two negative integers is a positive integer.

Examples:

1. (-10) x (-12) = 120

2. (-15) x (-6) = 90

3. (-3) x (-4) = 12.

**III . Product of three or more Negative Integers**:

If the number of negative integers in a product is even, then the product is a positive integer; if the number of negative integers in a product is odd, then the product is a negative integer.

Examples:

1. (-4) x (-3) x (-2) = -24

2. (-4) x (-3) x (-2) x (-1) = 24

3. 9 x (-2) x (-3) = 54

**Practice Problems:**

Find each of the following products:

1. (-8) x 7

2. (-75) x (-2)

3. (-4) x 0 x (-2)

4. 3 x (-8) x (-1)

5. (-5) x (-2) x (-1)

All the sums are very useful