NCERT solutions for Mathematics [English] Class 7 chapter 1 - Integers [Latest edition]

Write down the pair of integers whose sum is −7.

Write down the pair of integers whose difference is −10.

Write down the pair of integers whose sum is 0.

Write a pair of negative integers whose difference gives 8.

Write a negative integer and a positive integer whose sum is −5.

Write a negative integer and a positive integer whose difference is −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?

Fill in the blank to make the following statement true:

(−5) + (−8) = (−8) + (______)

Fill in the blank to make the following statement true:

−53 + ______ = −53

Fill in the blank to make the following statement true:

17 + ______ = 0

Fill in the blank to make the following statement true:

[13 + (−12)] + (______) = 13 + [(−12) + (−7)]

Fill in the blank to make the following statement true:

(−4) + [15 + (−3)] = [−4 + 15] + ______

Find the following product:

3 × (−1)

Find the following product:

(−1) × 225

Find the following product:

(−21) × (−30)

Find the following product: 

(−316) × (−1)

Find the following product:

(−15) × 0 × (−18)

Find the following product:

(−12) × (−11) × (10)

Find the following product:

9 × (−3) × (−6)

Find the following product:

(−18) × (−5) × (−4)

Find the following product:

(−1) × (−2) × (−3) × 4

Find the following product:

(−3) × (−6) × (−2) × (−1)

Verify the following: 

18 × [7 + (–3)] = [18 × 7] + [18 × (–3)]

Verify the following:

(–21) × [(– 4) + (– 6)] = [(–21) × (– 4)] + [(–21) × (– 6)]

For any integer a, what is (− 1) × a equal to?

Determine the integer whose product with (−1) is −22.

Determine the integer whose product with (–1) is 37.

Determine the integer whose product with (–1) is 0.

Evaluate the following:

(–30) ÷ 10

Evaluate the following:

50 ÷ (–5)

Evaluate the following:

(–36) ÷ (–9)

Evaluate the following:

(– 49) ÷ (49)

Evaluate the following:

13 ÷ [(–2) + 1]

Evaluate the following:

0 ÷ (–12)

Evaluate the following:

(–31) ÷ [(–30) + (–1)]

Evaluate the following:

[(–36) ÷ 12] ÷ 3

Evaluate the following:

[(– 6) + 5)] ÷ [(–2) + 1]

Verify that a ÷ (b + c) ≠ (a ÷ b) + (a ÷ c) for the following values of a, b and c.

a = 12, b = −4, c = 2

Verify that a ÷ (b + c) ≠ (a ÷ b) + (a ÷ c) for the following values of a, b and c.

a = (−10), b = 1, c = 1

369 ÷ _____ = 369

(–75) ÷ _____ = –1

(–206) ÷ _____ = 1

– 87 ÷ _____ = 87

_____ ÷ 1 = – 87

______ ÷ 48 = –1

20 ÷ _____ = –2

______ ÷ (4) = –3

Write five pairs of integers (a, b) such a ÷ b = −3. One such pair is (6, −2) because 6 ÷ (−2) = (−3).

The temperature at 12 noon was 10°C above zero. If it decreases at the rate of 2°C per hour until midnight, at what time would the temperature be 8°C below zero? What would be the temperature at midnight?

In a class test (+3) marks are given for every correct answer and (–2) marks are given for every incorrect answer and no marks for not attempting any question. Radhika scored 20 marks. If she has got 12 correct answers, how many questions has she attempted incorrectly? 

In a class test (+3) marks are given for every correct answer and (–2) marks are given for every incorrect answer and no marks for not attempting any question. Mohini scores –5 marks in this test, though she has got 7 correct answers. How many questions has she attempted incorrectly?

An elevator descends into a mine shaft at the rate of 6 m/min. If the descent starts from 10 m above the ground level, how long will it take to reach −350 m?