Integers exercise 1.1 solutions class 7 maths NCERT
NCERT class 7 maths chapter 1 exercise 1.1 solutions are given.
You should study the textbook lesson Integers very well.
You should also practice all problems and solutions given in the textbook.
Observe the solutions and try them in your own method.
Exercise 1.1 Integers solutions maths 7th class NCERT
Chapter 1
Integers
EXERCISE 1. 1
1. Write down a pair of integers whose:
a. Sum is – 7.
b. Difference is – 10.
c. Sum is 0
Solutions:
a. Sum is – 7.
(- 3) + (- 4) = – 3 – 4 = – 7 or
( -5) + (- 2) = – 5 – 2 = – 7
b. Difference is – 10.
(- 15) – (- 5) = – 15 + 5 = – 10 or
(- 18) – (- 8) = – 18 + 8 = – 10
c. Sum is 0
(- 6) + 6 = 0 or
(- 3) + 3 = 0
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.
Solutions:
a. (- 4) – (- 12) = – 4 + 12 = 8
b. (- 9) + 4 = – 9 + 4 = – 5
c. (- 2) – (+1) = – 2 – 1 = – 3
3. In a quiz, team A scored – 40, 10, 0 and team scored 10, 0, – 40 in three successive rounds. Which team scored more? Can we day that we can add integers in any order?
Solution:
The scores of team A = – 40, 10 and 0
The scores of team B = 10, 0 and – 40
The total score of team A = – 40 + 10 + 0 = – 30
The total score of team B = 10 + 0 + (- 40) = – 30
The scores of both the teams are equal.
Yes, we observe that the scores got by both teams in successive rounds are numerically equal. But they are different in order.
Problem:
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] + ……..
Solutions:
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)
Note: Observe the solutions and try them in your own method.