CBSE NCERT Solutions for Class 7 Chapter 1

Chapter-wise, thorough solutions to the questions of the NCERT textbooks are provided with the aim of helping students compare their answers. NCERT Solutions for Class 7 provide detailed explanations for all the questions provided in the NCERT textbooks set for class 7 CBSE schools.

CBSE NCERT Solutions for Class 7 Maths Chapter 1:

Question-1:

At Srinagar temperature was −5° C on Monday and then it dropped by 2° C on Tuesday. What was the temperature of Srinagar on Tuesday? On Wednesday, it rose by 4°C. What was the temperature on this day?

Solution:

Temperature on Monday =−5°C
Temperature on Tuesday = Temperature on Monday−2°C
=−5°C−2°C=−7°C
Temperature on Wednesday = Temperature on Tuesday +4°C
=−7°C+4°C=−3°C
Therefore, the temperature on Tuesday and Wednesday was −7o C and −3o C respectively.

Question-2:

In a quiz, team A scored 40,10,0 and team B scored 100−40 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.
Total score = − 40 + 10 +0
=−30
Team B scored 10, 0,−40.
Total score = 10 + 0 +(−40)
=−30
∴ The scores of both teams are equal.
Yes, we can add integers in any order. We had observed that the scores obtained by both teams in successive rounds were numerically equal but different in order. Yet, the total score of both teams were equal.

Question-3:

Find each of the following products:
(a) 3×(−1)
(b) (−1)×225
(c) (−21)×(−30)
(d) (−316)×(−1)
(e) (−15)×0×(−18)
(f) (−12)×(−11)×(10)
(g) 9×(−3)×(−6)
(h) (−18)×(−5)×(−4)
(i) (−1)×(−2)×(−3)×4
(j) (−3)×(−6)×(−2)×(−1)

Solution:

(a) 3 × (−1) =−3
(b) (−1) × 225 =−225
(c) (−21) × (−30) =630
(d) (−316) × (−1) =316
(e) (−15)×0×(−18)=0
(f) (−12) × (−11) × 10 =1320
(g) 9×(−3)×(−6)=162
(h) (−18)×(−5)×(−4)=−360
(i) (−1)×(−2)×(−3)×4=−24
(j) (−3)×(−6)×(−2)×(−1)=36