CBSE Class 7 Mathematics Integers Worksheet Set B

Question: Verify and name the property used :
(i) –117 × 251 + (–117) × 249
(ii) 156 × 273 – 156 × (–73)
Answer: (i) Distributive property of multiplication over addition
(ii) Distributive property of multiplication over subtraction 

Question: The temperature at 12 noon was 10°C above zero. At what time the temperature will be 8°C below 0°C, if it decreases at the rate of 2°C ? If it decreases at the rate of 2°C per hour till midnight, what would be the temperature at mid-night ?
Answer: 9 pm, –14ºC

Question: Write the value of
(i) | +22 |
(ii) | –8 |
(iii) | 18 – 8 |
(iv) | – 5 – 4 |
(v) – | 3 – 2 |
Answer: (i) 22
(ii) 8
(iii) 10
(iv) 9 (v) –1

Question: A boy has j- 350 in his bank account. He deposits j- 40 everyday for 10 days. What will be the amount in his account at the end of 10 days ?
Answer: j- 750

Question: Verify and name the property used :
(i) –110 × (–237) = (–237) × (–110)
(ii) (–35 × 4) × (–152) = –35 × [4 × (–152)]
Answer: (i) Commutative property of multiplication.
(ii) Associative property of multiplication.

Question: Arrange the following integers in ascending order
(i) – 20, 13, 4, 0, –5, +5
(ii) +30, –2, 0, –6, –20, 8
Answer: (i) –20, –5, 0, 4, 5, 13
(ii) –20, –6, –2, 0, 8, 30

Question: 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 questions.
(i) Ram scored 20 marks. If he has got 12 correct answers, how many questions has he attempted  incorrectly ?
(ii) Mohan scores –5 marks in the test though he has written 7 correct answers. How many questions has he attempted incorrectly ?
Answer: (i) 8
(ii) 13

Question: A water tank has steps inside it. A monkey is sitting on the toppest step (i.e., the first step). The water level is at the ninth step.
(i) He jumps 3 steps down and then jumps 2 steps up. If he continues in this way, in how many jumps will he reach the water level ?
(ii) After drinking water, he wants to go back, for this he jumps 4 steps up and then jumps 2 steps down in every move. In how many jumps will he reach back the top step ?
Answer: (i) 11 times
(ii) 5 times

Question: In a class test containing 10 questions, 5 marks are answered for every correct answer and (–2) marks are awarded for every incorrect answer and 0 for questions not attempted .
(i) Mohan gets four correct and six incorrect answers. What is his score ?
(ii) Reshma gets five correct answer and five incorrect answers. What is her score ?
(iii) Heena gets two correct and five incorrect answers out of seven questions she attempts. What is her score ?
Answer: (i) 8 marks
(ii) 15 marks
(iii) 0 mark

Question: Which temperature is higher ?
(i) 40°C or –40°C
(ii) –18°C or 12°C
(iii) –2°C or –4°C
(iv) 17°C or 27°C
Answer: (i) 40ºC
(ii) 12ºC
(iii) –2ºC
(iv) 27ºC

Question: Evaluate the following :
(i) (– 40) ÷ 10
(ii) 60 ÷ (–6)
(iii) (– 49) ÷ (–7)
(iv) (–79) ÷ 79
(v) 13 ÷ [(–4) + 3]
(vi) 0 ÷ (–14)
(vii) (– 41) ÷ [(– 40) + (–1)]
(viii) [(– 48) ÷ 12] ÷ 4
(ix) Is [(–7) + (6)] = [(–3) + 2] ?
Answer: (i) –4
(ii) –10
(iii) 7
(iv) –1
(v) –13
(vi) 0
(vii) 1
(viii) –1
(ix) yes

Question: Write down a pair of integers whose :
(i) sum is – 7
(ii) difference is –10
(iii) sum is 0
Answer: (i) –1, –6 or –9, 2
(ii) –11, –1 or 35, –45
(iii) –1, 1 or 20, –20