Class-6 Subject-Maths Chapter-1 Slot-1 Knowing Our Numbers (Ex1.1)

 

EVENTS CONVENT HIGH SCHOOL
31/07/2021          CLASS-6         SESSION2021-22(SLOT-1)
Maths
Chapter-1
Knowing our Numbers
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Knowing our Numbers Chapter Explanation

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Question 1.Fill in the blanks:

(a) 1 lakh = ………….. ten thousand.

(b) 1 million = ………… hundred thousand.

(c) 1 crore = ………… ten lakh.

(d) 1 crore = ………… million.

(e) 1 million = ………… lakh.

Solution:

(a) 1 lakh = ten ten thousand.

(b) 1 million = ten hundred thousand.

(c) 1 crore = ten ten lakh

(d) 1 crore = ten million

(e) 1 million = ten lakh

 

Question 2.Place commas correctly and write the numerals:

(a) Seventy-three lakh seventy-five thousand three hundred seven.

(b) Nine crore five lakh forty-one.

(c) Seven crore fifty-two lakh twenty-one thousand three hundred two.

(d) Fifty-eight million four hundred twenty- three thousand two hundred two.

(e) Twenty-three lakh thirty thousand ten.

Solution:

(a) 73,75,307

(b) 9,05,00,041

(c) 7,52,21,302

(d) 5,84,23,202

(e) 23,30,010.

 

Question 3.Insert commas suitably and write the names according to Indian System of Numeration:

(a) 87595762

(b) 8546283

(c) 99900046

(d) 98432701

Solution:

(a) 8,75,95,762 (Eight crore seventy-five lakh ninety-five thousand seven hundred sixty- two)

(b) 85,46,283 (Eighty-five lakh forty-six thousand two hundred eighty-three)

(c) 9,99,00,046 (Nine crore ninety-nine lakh forty-six)

(d) 9,84,32,701 (Nine crore eighty-four lakh thirty-two thousand seven hundred one)

 

Question 4.Insert commas suitably and write the names according to International System of Numeration:

(a) 78921092

(b) 7452283

(c) 99985102

(d) 48049831

Solution:

(a) 78,921,092 (Seventy-eight million nine hundred twenty-one thousand ninety-two)

(b) 7,452,283 (Seven million four hundred fifty- two thousand two hundred eighty-three)

(c) 99,985,102 (Ninety-nine million nine hundred eighty-five thousand one hundred two)

(d) 48,049,831 (Forty-eight million forty-nine thousand eight hundred thirty-one)

Class-7 Subject-Maths Chapter-1 Slot-1 INTEGERS(Ex1.1)

 

EVENTS CONVENT HIGH SCHOOL
31/07/2021          CLASS-7         SESSION2021-22(SLOT-1)
Maths
Chapter-1(EX.1.1)
INTEGERS
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INTRODUCTION INTEGERS 

Que-1 Explain
Que-2 Explain
Que-3 Explain
Que-4 Explain
Que-5 Explain
Que-8 Explain
Que-9 Explain

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.

(b) What is the temperature difference between the hottest and the coldest places among the above?

(c) What is the temperature difference between Lahulspriti and Srinagar?

 

Cities                            Temperature

Lahulspriti -                           8°C

Srinagar     -                           2°C

Shimla                                    5°C

 (b) The temperature of the hottest place = 22°C

The temperature of the coldest place = -8°C

Difference = 22°C – (-8°C)

= 22°C + 8°C = 30°C

(c) Temperature of Lahulspriti = -8°C

Temperature of Srinagar = -2°C

∴ Difference = -2°C – (-8°C)

= -2°C + 8°C = 6°C

 

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:

Given scores are 25, -5, -10, 15, 10

Marks given for correct answers

= 25 + 15 + 10 = 50

Marks given for incorrect answers

= (-5) + (-10) = -15

∴ Total marks given at the end

= 50 + (-15) = 50 – 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:

Initial temperature of Srinagar on Monday = -5°C

Temperature on Tuesday = -5°C – 2°C = -7°C

Temperature was increased by 4°C on Wednesday.

∴ Temperature on Wednesday

= -7°C + 4°C = -3°C

Hence, the required temperature on Tuesday = -7°C

and the temperature on Wednesday = -3°C

 

Question 4.A plane is flying at the height of 5000 m above the sea level. At a particular point, it is exactly above a submarine flowing 1200 m below the sea level. What is the vertical distance between them?

Solution:

Height of the flying plane = 5000 m

Depth of the submarine = -1200 m

∴ Distance between them

= + 5000 m – (-1200 m)

= 5000 m + 1200 m = 6200 m

Hence, the vertical distance = 6200 m

 

 

Question 5.Mohan deposits ₹ 2,000 in a bank account and withdraws ₹ 1,642 from it, the next day. If 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:

The deposited amount will be represented by a positive integer i.e., ₹ 2000.

Amount withdrawn = ₹ 1,642

∴ Balance in the account

= ₹ 2,000 – ₹ 1,642 = ₹ 358

Hence, the balance in Mohan’s account after the withdrawal

= ₹ 358

 

Question 8.Verify a – (-b) = a + b for the following values of a and 6.

(i) a = 21, b = 18

(ii) a = 118, b = 125

(iii) a = 75, b = 84

(iv) a= 28, 6 = 11

Solution:

(i) a – (-b) = a + b

LHS = 21 – (-18) = 21 + 18 = 39

RHS = 21 + 18 = 39

LHS = RHS Hence, verified.

 

(ii) a – (-b) = a + b

LHS = 118 – (-125) = 118 + 125 = 243

RHS = 118 + 125 = 243

LHS = RHS Hence, verified.

 

(iii) a – (-b) = a + b

LHS = 75 – (-84) = 75 + 84 = 159

RHS = 75 + 84 = 159

LHS = RHS Hence, verified.

 

 Question 9.Use the sign of >, < or = in the box to make the statements true.

(a) (-8) +(-4) □(-8)-(-4)

(b) (-3) + 7 – (19) □ 15 – 8 + (-9)

(c) 23 – 41 + 11 □ 23 – 41 – 11

(d) 39 + (-24) – (15) □ 36 + (-52) – (-36)

(e) -231 + 79 + 51 □ -399 + 159 + 81

Solution:

(a) (-8) + (-4) □ (-8) – (-4)

LHS = (-8) + (-4) = -8 – 4 = – 12

RHS = (-8) – (-4) = -8 + 4 = -4

Here – 12 < -4

Hence, (-8) + (-4) [<] (-8) – (-4)

 

(b) (-3) + 7 – (19) □ 15 – 8 + (-9)

LHS = (-3) + 7 – (19) =-3 + 7-19

= -3 – 19 + 7

= -22 + 1 = -15

RHS = 15 – 8 + (-9)

= 15-8-9

= 15 – 17 = -2

Here -15 < -2

Hence, (-3) + 7 – (19) [<] 15 – 8 + (-9)

 

(c) 23 – 41 + 11 □ 23 – 41 – 11

LHS = 23 – 41 + 11 = 23 + 11 – 41 = 34 – 41 = -7

RHS = 23 – 41 – 11 = 23 – 52 = -29 Here, -7 > -29

Hence, 23 – 41 + 11 [>] 23 – 41 – 11

Class-8 Subject-Maths Chapter-1 Slot-1 Rational Numbers(Ex1.1)

 

EVENTS CONVENT HIGH SCHOOL
31/07/2021          CLASS-8         SESSION2021-22(SLOT-1)
Maths
Chapter-1(E.X1.1)
Rational Numbers
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EXPLANATION EX 1.1