7_4_1_T

© 2009 -2011 tutorco.com 1 GRADE 7 TOPIC: INTEGERS 7/4/1/T Specific Objectives: • Student will learn the meaning of positive and negative numbers and their relevance in every day life. • Student will be able to plot numbers on the number line, both positive and negative numbers. • Student will be able to find the absolute value of numbers. Key Concept: Understanding the concept of integers, number line and absolute value. Plan of action: The first numbers to be discovered were natural numbers i.e. 1, 2, 3, 4, If we include zero to the collection of natural numbers, we get a new collection of numbers known as whole numbers i.e. 0, 1, 2, 3, 4 and so on. If we put the whole numbers and the negative numbers together, the new collection of numbers will look like 0, 1, 2, 3, 4, 5,..., –1, – 2, – 3, –4, –5... This collection of numbers is known as Integers. In this collection, 1, 2, 3 ... are said to be positive integers and – 1, – 2, – 3, are said to be negative integers. The collection of integers can be understood by the following diagram in which all the class of numbers are included: What they already know: Student knows about: • Natural Numbers. • Whole Numbers. © 2009 -2011 tutorco.com 2 Suggested examples: We will learn how to represent integers on a number line. Draw a line and mark some points at equal distance on it as shown in the figure. Mark a point as zero on it. Points to the right of zero are positive integers and are marked + 1, + 2, + 3, etc. or simply 1, 2, 3 etc. Points to the left of zero are negative integers and are marked – 1, – 2, – 3 etc. Example 1 : Write 3 integers between -8 and -2. Answer : -7,-6, -3. Example 2 : Represent 25°C below 0°C with appropria te sign. Answer : -25°C Example 3 : Find the absolute value of the numbers -11,-22, 44 and 55 Answer : 11, 22, 44 and 55.