KSEEB Solutions for Class 7 Maths Chapter 1 Integers Ex 1.2

KSEEB Solutions for Class 7 Maths Chapter 1 Integers Ex 1.2

Karnataka State Syllabus Class 7 Maths Chapter 1 Integers Ex 1.2

Question 1.
Write down a pair of integers whose:

a) sum is – 7
– 2 + – 5 = – 7
∴ The two integers be – 2 and – 5.

b) difference is – 7
– 20 – (- 10) = – 10 (∵ – 20 – (- 10))
– 20 + 10 = – 10
∴ The two integers be – 20 and – 10.

c) sum is 0
Any two integers of same number but different sign.
For eg : 10 + (- 10) = 0.

Question 2.
a) Write a pair of negative integers whose difference gives 8.
Solution:
Let -4 and -12 are two negative integers.
∴ -4 – (-12)
-4 + 12 = 8

b) Write a negative integer and a positive integer whose sum is -5.
Solution:
Let -10 and 5
∴  -10 + 5 = -5

c) Write a negative integer and a positive integer whose difference is -3.
Solution:
Let -2 and 1
-2 – (+1)
-2 – 1 = -3

Question 3.
In a quiz, team A scored -40, 10, 0 and team B scored 10, 0, – 40 in three successive rounds. Which team scored more? Can we say that we can add integers in any order?
Solution:
Team A scored = – 40 + 10 + 0 = – 30
TeamB scored = 10 + 0 – 40 = – 30
Yes. We can add integers in any order.

Question 4.
Fill in the blanks to make the following statements true :
i) (-5) + (-8) = (-8) + (……..)
(-5) + (-8) = (-8) + (-5)

ii) 53 + = – 53
-53 + 0 = -53

iii) 17 + …. 0
17 + -17 = 0

iv) 113 + (-12) + (……) = 13 + [(-12) + (-7)]
[13 + (-12) + (-7) = 13 + [(-12) + (-7)]

v) (-4) + [15 + (-3)] = [-4 + 15] + -3
(-4) + [15 + (-3)] = [-4 + 15] + -3.