Important Questions for Class 7 Maths Chapter 1 : Class 7 Maths Chapter 1 Integers, is a foundational topic that helps students understand positive and negative numbers, their properties, and operations.
Important questions from this chapter often focus on addition, subtraction, multiplication, and division of integers. Problems may include applying rules for operations with integers, comparing and ordering integers, and solving word problems involving real-life situations like temperature changes, profit and loss, or elevation differences. Mastering this chapter is essential for building a strong base in mathematics, as it forms the groundwork for higher-level topics in algebra and data handling.Important Questions for Class 7 Maths Chapter 1 PDF
Very Short Answer Questions (1 Mark)
1. What is the additive inverse of -9?
Solution: Additive inverse of -9 = 9.
2. Find the value of (-6) + (+3).
Solution: (-6) + (+3) = -3.
3. What is the product of (-4) × (0)?
Solution: (-4) × (0) = 0.
4. Fill the blanks for -22 × -13 × 5= -22 × -13 × 5= _____
Solution: 1430 1430
5. Fill the blanks for -3 × 125= -3 × 125= ___
Solution: 375 -375
Short Answer Questions (2-3 Marks)
1. Simplify: (-7) + (+8) + (-3).
Solution: (-7) + (+8) + (-3) = -7 + 8 - 3
= 1 - 3 = -22. Find the value of (-15) × (-4) + (+20).
Solution: (-15) × (-4) + (+20)
= 60 + 20 = 803. Subtract: (-10) from (+15).
Solution: 15 - (-10) = 15 + 10 = 25
4. Write down a pair of integers for the following
a. Sum gives -9 -9
Solution: A pair of integers that gives sum -9 -9 is ( − 6 , − 3 ) (−6,−3) .
b. Difference gives -11 -11
Solution : A pair of integers that gives sum -11 -11 is ( − 14 , 3 ) (−14,3) .
5. a. Write a positive and negative integer whose sum is -4 -4 .
Solution: ( 4 , − 8 ) (4,−8) is a positive and negative integer whose sum is -4 -4 .
b.Write a negative integer and a positive integer whose difference is -2 -2 .
Solution: ( − 1 , 1 ) (−1,1) is a positive and negative integer whose sum is -2 -2 .
Long Answer Questions (4-5 Marks)
1. A submarine is at a depth of 300 m below sea level. It rises 125 m and then descends 50 m. What is its current position?
Solution:
Initial position = -300 m (below sea level) Rising 125 m = -300 + 125 = -175 m Descending 50 m = -175 - 50 = -225 m Current position = 225 m below sea level2. Verify: (-3) × [(-4) + 5] = [(-3) × (-4)] + [(-3) × 5].
Solution: LHS = (-3) × [(-4) + 5] = (-3) × (1) = -3
RHS = [(-3) × (-4)] + [(-3) × 5] = 12 + (-15) = -3 LHS = RHS. Verified!3. A temperature of a place at 12 PM was 6°C. By 4 PM, it dropped by 12°C, and by 8 PM, it rose by 7°C. What was the temperature at 8 PM?
Solution: Temperature at 12 PM = 6°C
Drop by 12°C = 6 - 12 = -6°C Rise by 7°C = -6 + 7 = 1°C Temperature at 8 PM = 1°C4. Verify that
for each of the following values of a,b a,b and c c .
a. a=8, b=4, c=2 a=8,b=4,c=2
Solution: For equation
L.H.S
= ( 8 ÷ -4 ) + ( 8 ÷ 2 ) =(8 ÷ -4)+(8 ÷ 2)
=-2+4 =-2+4
=2 =2
Hence, L .H .S ≠ R .H .S L.H.S≠R.H.S .
Thus,
for a=8, b=4, c=2 a=8,b=4,c=2 .
b. a=-15, b=2, c=1 a=-15,b=2,c=1
Solution: For equation
L.H.S
=-15 ÷ ( 2+1 ) =-15 ÷ (2+1)
=-15 ÷ 3 =-15 ÷ 3
=-5 =-5
R.H.S
= ( -15 ÷ 2 ) + ( -15 ÷ 1 ) =(-15 ÷ 2)+(-15 ÷ 1)
=-7 .5+ ( -15 ) =-7.5+(-15)
=-22 .5 =-22.5
Hence, L .H .S ≠ R .H .S L.H.S≠R.H.S
Thus,
for a=-15, b=2, c=1 a=-15,b=2,c=1 .
5. In a CET Examination ( +2 ) (+2) marks are given for every current answer and ( -0 .5 ) (-0.5) marks are given for every wrong answer and 0 0 for non-attempting any question.
a. Likitha scores 30 30 marks. If she got 20 20 correct answers, how many questions she has attempted incorrectly?
Solution: Marks obtained for 1 1 correct answer =+2 =+2
Marks obtained for 1 1 wrong answer =-0 .5 =-0.5
So, Marks scored by Likitha = 30 30
Marks obtained by 20 20 correct answers = 20 × 2 = 40 =20×2=40
Marks obtained for incorrect answer = = Total score − − Marks obtained by 20 20 correct answer
= 30 − 40 =30−40
= − 10 =−10
Marks obtained for 1 1 wrong answer = − 0.5 =−0.5
∴ ∴ The number of incorrect answers = − 10 − 0.5 =−10−0.5
= 20 =20
Hence, she attempted 20 20 questions wrongly.
b. Saara scores -4 -4 marks if she got 3 3 correct answers. How many were incorrect?
Ans: Marks obtained for 1 1 correct answer =+2 =+2
Marks obtained for 1 1 wrong answer =-0 .5 =-0.5
So, Marks scored by Saara = − 4 =−4
Marks obtained for 3 correct answers = 3 × 2 = 6 =3×2=6
Marks obtained for incorrect answers = = Total score − − Marks obtained for 3 3 correct answer
= − 4 − 6 = − 10 =−4−6=−10
Marks obtained for 1 wrong answer = − 0.5 =−0.5
∴ ∴ The number of incorrect questions = − 10 − 0.5 =−10−0.5
= 20 =20
Hence, 20 20 questions were incorrect.