Page 118 - ICSE Math 5

Solution: (a) On the number line 10 is to the right of 4.
(b) On the number line 0 is to the right of –1.

Example 7: Arrange 5, –2, 1, –1 and 0 in ascending and descending orders using a number line.
–2 –1 0 1 5

Solution:
–10 –9 –8 –7 –6 –5 –4 –3 –2 –1 0 1 2 3 4 5 6 7 8 9 10

Ascending order of the given integers is –2 < –1 < 0 < 1 < 5.

Descending order of the given integers is 5 > 1 > 0 > –1 > –5.
Example 8: Write the next four negative integers greater than –4.

Solution: –3, –2, –1 and 0

Exercise 8.2

1. Write all the integers between the given pairs of integers using a number line.

(a) –4 and 4 (b) –10 and 0 (c) –9 and –5 (d) 1 and 12

2. Which integer in each of the following pairs is to the left of the other on the number line?

(a) 0, 6 (b) –4, 12 (c) –4, –6 (d) –12, –10

3. Write the next three negative integers greater than –7.

4. Write any three negative integers less than 1.

5. Arrange the following integers in increasing order.

(a) 0, –2, 5, 6, –4 (b) –10, 1, 10, 15, –20 (c) –13, –11, 13, –4, 11

6. Arrange the following integers in decreasing order.

(a) 4, –3, 1, –2, –10 (b) –18, –9, 2, 18, –27 (c) –10, –16, 17, 14, 9

7. Fill in the blanks with appropriate symbol ‘>’ or ‘<’.

(a) –3 ____ –4 (b) –10 ____ 10 (c) 2 ____ 5 (d) –2 ____ 9
Addition and Subtraction of Integers

Let’s learn how to add and subtract integers with and without using a number line.
Addition of Integers on a Number Line

Addition of two positive integers

When both the addends are positive integers, first move to the right of 0 to reach the first addend
and then again to the right of the first addend to find the sum.

108