Students can Download Class 7 Maths Chapter 1 Integers Ex 1.1 Questions and Answers, Notes Pdf, KSEEB Solutions for Class 7 Maths helps you to revise the complete Karnataka State Board Syllabus and to clear all their doubts, score well in final exams.
Karnataka State Syllabus Class 7 Maths Chapter 1 Integers Ex 1.1
Question 1.
Following number line shows the temperature in degree Celsius (°C) at different places on a particular day.
a) Observe this number line and write the temperature of the places marked on it.
Solution:
Lahulspiti = -8°C, Srinagar = -2°C, Shimla = 5°C, Ooty = 14°C, Bengaluru = 22°C.
(b) What is the temperature difference between the hottest and the coldest places among the above?
Solution:
Hottest place is Bengaluru = 22°C
Coldest place is Lahulspiti = – 8°C
Temperature difference between them is
= 22°C-(-8°C) = 30°C.
= 22°C + 8°C = 30°C.
(c) What is the temperature difference between Lahulspiti and Srinagar?
Solution:
Temperature at Lahulspiti = -8°C Temperature at Srinagar = -2°C Difference = -8°C – (-2°C)
= – 8°C + 2°C = -6°C.
(d) Can we say the temperature of Srinagar and Shimla taken together is less than the temperature at Shimla? Is it also less than the temperature at Srinagar?
Solution:
The temperature of Srinagar and Shimla took together = -2°C + 5°C = 3°C
Yes, it is also less than the temperature at Srinagar.
Question 2.
In a quiz, positive marks are given for correct answers, and negative marks are given for incorrect answers. If Jack’s scores in five successive rounds were 25, – 5, – 10, 15, and 10, what was his total at the end?
Solution:
The scores of five successive rounds = 25, – 5, – 10, 15, 10
Total scores of Jack at the end of the event
= 25 + 15 + 10 + = 50
= – 5 – 10 = – 15
= 35
Question 3.
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:
The temperature on Monday at Srinagar = – 5°C
The temperature on Tuesday at Srinagar = – 5 – 2 = – 7° C
The temperature on Wednesday at Srinagar = – 7 + 4 = – 3° C
Question 4.
A plane is flying at a height of 5000 m above the sea level. At a particular point, it is exactly above a submarine floating 1200m below the sea level. What is the vertical distance between them?
Solution:
The height of the plane flying above sea level = 5000 m.
Depth of the Submarine Floating below the sea-level = 1200 m.
∴ The vertical distance between them = 6200 m.
Question 5.
Mohan deposits 2,000 in his bank account and withdraws 1,642 from it, the next day. If the withdrawal of amount from the account is represented by a negative integer, then how will you represent the amount deposited? Find the balance in Mohan’s account after the withdrawal.
Solution:
Amount deposited in the Bank by Mohan = Rs. 2000
Amount withdrawal from the Bank by Mohan = Rs. 1642
Balance amount after the withdrawal = Rs. 358
From the number line, the Balance amount represents the distance B to A.
B to A = Rs. 358.
Question 7.
In a magic square each row, column and diagonal have the same sum. Check which of the following is a magic square.
Solution:
(ii) is a magic square.
Question 8.
Verify a – (- b) = a + b for the following values of a and b.
i) a = 21, b = 18
Solution:
a – (- b) – a + b
21 – (- 18) = 21 + 18
21 + 18 = 21 + 18 = 39,
(ii) a = 118, b = 125
Solution:
a – (- b) = a + b
118 – (- 125) = 118 + 125
118 + 125 = 118 + 125
= 243.
(iii) a = 15, b = 84
Solution:
a – ( – b) = a + b
75 – ( – 84) = 75 + 84
75 + 84 = 75 + 84
159 = 159.
(iv) a = 28, b = 11
Solution:
a – ( – b) = a + b
28 – ( – 11) = 28 + 11
28 + 11 = 28 + 11
39 = 39
Question 9.
Use the sign of >, < or = in the box to make the statements true.
Solution:
Question 10.
A water tank has stepped inside it. A monkey is sitting on the topmost step (i.e., the first step). The water level is at the ninth step.
i) He jumps 3 steps down and then jumps back 2 steps up. In how many jumps will he reach the water level?
Solution:
He will reach the water level in 11 jumps.
(ii) After drinking water, he wants to go back. For this, he jumps 4 steps up and then jumps back 2 steps down in every move. In how many jumps will he reach back the top step?
Solution:
He will reach back the top step in 5 jumps.
(iii) If the number of steps moved down is represented by negative integers and the number of steps moved up by positive integers, represent his moves in part (i) and (ii) by completing the following:
(a) – 3 + 2…. = – 8
(b) 4 – 2 +…. = 8.
In (a) the sum (- 8) represents going down by eight steps. So, what will the sum 8 in (b) represent?
Solution:
(a) – 3 + 2 – 3 + 2 – 3 + 2 – 3 + 2 – 3 + 2 – 3 = – 8
(b) 4 – 2 + 4 – 2 + 4 = 8
8 in (b) represents going up by 8 steps.