- NCERT Solutions for Class 7 Maths Chapter 1 Integers Ex 1.1
- NCERT Solutions for Class 7 Maths Chapter 1 Integers Ex 1.2
- NCERT Solutions for Class 7 Maths Chapter 1 Integers Ex 1.3
NCERT Solutions for Class 7 Maths Chapter 1 Integers Ex 1.1 (Rationalised Contents)
Ex 1.1 Class 7 Maths Question 1.
Write down a pair of integers whose:
(a) sum is -7
(b) difference is -10
(c) sum is 0
Solution.
(a) A pair of integers whose sum is -7 can be (-2) and (-5). Answers may vary.
∵ (-2) + (-5) = -7
(b) A pair of integers whose difference is -10 can be (-13) and (-3). Answers may vary.
∵ -13 – (-3) = -13 + 3 = -10
(c) A pair of integers whose sum is 0 can be 5 and (-5). Answers may vary.
∵ (-5) + (5) = 0
Ex 1.1 Class 7 Maths Question 2.
(a) Write a pair of negative integers whose difference gives 8.
(b) Write a negative integer and a positive integer whose sum is -5.
(c) Write a negative integer and a positive integer whose difference is -3.
Solution.
(a) A pair of negative integers whose difference gives 8 can be -2 and -10. Answers may vary.
∵ (-2) – (-10) = -2 + 10 = 8
(b) A negative integer and a positive integer whose sum is -5 can be -10 and 5. Answers may vary.
∵ (-10) + 5 = -10 + 5 = -5
(c) A negative integer and a positive integer whose difference is -3 can be -2 and 1. Answers may vary.
∵ (-2) – 1 = –2 – 1 = -3
Ex 1.1 Class 7 Maths 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.
Total score of team A = (-40) + 10 + 0
= -40 + 10 + 0 = -30
Total score of team B = 10 + 0 + (-40)
= 10 + 0 – 40 = -30
Since, the total score of each team is equal.
∴ No team scored more than the other but each team has equal score.
Yes, we can add integers in any order and the result remains the same. For example, (-40) + 10 + 0 = -30 = 10 + 0 + (-40)
Ex 1.1 Class 7 Maths Question 4.
Fill in the blanks to make the following statements true:
(i) (-5) + (-8) = (-8) + (………)
(ii) -53 + ……. = -53
(iii) 17 + …… = 0
(iv) [13 + (-12)] + (………..) = 13 + [(-12) + (-7)]
(v) (-4) + [15 + (-3)] = [-4 + 15] + …..…
Solution.
(i) (-5) + (-8) = (-8) + (-5)
(ii) -53 + 0 = -53
(iii) 17 + (-17) = 0
(iv) [13 + (-12)] + (-7) = 13 + [(-12) + (-7)]
(v) (-4) + [15 + (-3)] = [-4 + 15] + (-3)
Related Links:
NCERT Solutions for Maths Class 8
NCERT Solutions for Maths Class 9
NCERT Solutions for Maths Class 10