Class 6 Maths Chapter 2 Important Question Answers - Whole Numbers

Q1: If you’re on a diet and have a breakfast consisting of 150 calories, a lunch consisting of 350 calories, and a dinner consisting of 1000 calories, then find the sum of the calories consumed that day.
Ans: Breakfast consisting of 150 calories.
Lunch consisting of 350 calories.
Dinner consisting of 1000 calories.
The sum of the calories consumed that day is 150 + 350 + 1000 = 1500 calories.

Q2: A taxi driver filled his car petrol tank with 40 litres of petrol on Monday. The next day, he filled the tank with 50 litres of petrol. If the petrol costs Rs.44 per litre, how much did he spend in all on petrol?
Ans: Petrol filled on Monday = 40 litres.
Petrol filled the next day = 50 litres.
∴ Total petrol filled on the two days = 40 litres + 50 litres = 90 litres.
∴ Cost of petrol per litre = Rs.44
∴ Cost of 90 litres petrol = Rs.44 × 90 = Rs.3960.

Ans: 

Smallest 7 digit number = 1,000,000

Thus, the smallest 7 digit number is larger than the largest 6 digit number.

Again,

Difference between these two numbers = 1,000,000 – 999,999 = 1

Hence, the smallest seven-digit number is larger than the largest six-digit number by 1.

Ans: Greatest three-digit number = 999

Greatest two-digit number = 99

∴ Product of both numbers = 999 x 99 = 999 x (100 – 1)

= 999 x 100 – 999 x 1

= 99900 – 999 = 98901

Ans: Number of the large buildings = 25

Number of the floors = 15

Number of the apartments on each floor = 4

∴ Total number of the apartments in large buildings = 25 x 15 x 4

Number of small buildings = 40

Number of the floors = 9

Number of the apartments on each floor = 3

∴ Total number of the apartments in small buildings = 40 x 9 x 3

Hence, the number of apartments in total = 25 x 15 x 4 + 40 x 9 x 3 = 1500 + 1080 = 2580.

Ans: Number of total chairs = 85

Cost of one chair = ₹ 180

Cost of 85 chairs = ₹ (85 x 180)

Number of total tables = 25

Cost of one table = ₹ 140

Cost of 25 tables = ₹ (25 x 140)

Total amount of all chairs and tables = ₹(85 x 180 + 25 x 140)

= ₹ (15300 + 3500) = ₹ 18800

Money given in advance by principal = ₹ 2500

∴ Remaining money to be paid to the dealer = ₹ 18800 – ₹ 2500 = ₹ 16300

Ans: Total cost of 124 LED sets = ₹(38,540 x 124)

= ₹ [38,540 x (100 + 20 + 4)]

= ₹ [38,540 x 100 + 38,540 x 20 + 38,540 x 4]

= ₹ [38,54,000 + 7,70,800 + 1,54,160]

= ₹ 47,789,60

Q8: Find the product by suitable rearrangement:
(a) 8 × 391 × 125
(b) 2 × 1234 × 50
Ans: (a) 8 × 391 × 125 = 391× (125 × 8)
= 391 × 1000
= 391,000
(b) 2 × 1234 × 50 =1234 × (2 × 50)
= 1234 × 100
= 123,400

Q9: State true or false:
(a) All natural numbers are whole numbers.
(b) All whole numbers are natural numbers.
(c) The predecessor of a two digit number is never a single digit number.
(d) 1 is the smallest whole number.
Ans: (a) True
(b) False, every whole number except 0 is a natural number.
(c) False, the predecessor of 10 is 9.
(d) True

Q10: Match the following:

Ans:

Q11: Study the pattern:
1 × 8 + 1 = 9
12 × 8 + 2 = 98
Ans: 1 × 8 + 1 = 9
12 × 8 + 2 = 98
123 × 8 + 3 = 987
As the digit of the 1st number incresing gradually like 1, 12, 123 and the last digit of equation is also increasing like 1, 2, 3 so next pattern will be 123 ×
8 + 3 = 987
And the sum is also in decreasing order like 9, 98, 987
So the next pattern is 123 × 8 + 3 = 987

Q12: Ramesh ordered 10 cartons of chocolates to distribute among the class. Each carton holds 20 boxes and each box has 12 chocolates. How many chocolates did Ramesh order altogether?

Ans: Total Chocolates Ordered by Ramesh:

Number of cartons: 10

Number of boxes per carton: 20

Number of chocolates per box: 12

Total chocolates = 10 cartons × 20 boxes/carton × 12 chocolates/box = 10 × 20 × 12 = 2400

Ramesh ordered 2400 chocolates altogether.

Q13: Mukesh lives in a hostel that charges Rs 55 for dinner and Rs 45 for lunch. Find the money he has to pay for seven days.

Ans: Total Money Mukesh Has to Pay for Meals in Seven Days:

Cost of dinner per day: Rs 55

Cost of lunch per day: Rs 45

Total cost per day = Rs 55 + Rs 45 = Rs 100

Total cost for seven days = 7 days × Rs 100/day = Rs 700

Mukesh has to pay Rs 700 for meals in seven days.

Q14: A taxi driver filled his car petrol tank with 40 litres of petrol on Monday. The next day, he filled the tank with 50 litres of petrol. If the petrol costs Rs 44 per litre, how much did he spend in all on petrol?

Ans: Total Money Spent on Petrol by Taxi Driver:

Petrol on Monday: 40 litres

Petrol on Tuesday: 50 litres

Cost per litre: Rs 44

Total litres of petrol = 40 + 50 = 90 litres

Total cost = 90 litres × Rs 44/litre = Rs 3,960

The taxi driver spent Rs 3,960 on petrol.

Q15: A vendor supplies 32 litres of milk to a hotel in the morning and 68 litres of milk in the evening. If the milk costs Rs 15 per litre, how much money is due to the vendor per day?

Ans: Money Due to the Milk Vendor per Day:

Milk supplied in the morning: 32 litres

Milk supplied in the evening: 68 litres

Cost per litre: Rs 15

Total milk supplied per day = 32 + 68 = 100 litres

Total cost per day = 100 litres × Rs 15/litre = Rs 1,500

The money due to the vendor per day is Rs 1,500.

Q16: A person had Rs 1000000 with him. He purchased a colour T.V. for Rs 16580, a motor cycle for Rs 45890 and a flat for Rs 870000. How much money was left with him?

Ans: Money Left with the Person after Purchases:

Initial amount: Rs 1,000,000

Cost of T.V.: Rs 16,580

Cost of motorcycle: Rs 45,890

Cost of flat: Rs 870,000

Total spent = Rs 16,580 + Rs 45,890 + Rs 870,000 = Rs 932,470

Remaining amount = Rs 1,000,000 - Rs 932,470 = Rs 67,530

The money left with him is Rs 67,530.

Q17: Chinmay had Rs 610000. He gave Rs 87500 to Jyoti, Rs 126380 to Javed and Rs 350000 to John. How much money was left with him?

Ans: Money Left with Chinmay after Giving Away Money:

Initial amount: Rs 610,000

Amount given to Jyoti: Rs 87,500

Amount given to Javed: Rs 126,380

Amount given to John: Rs 350,000

Total given away = Rs 87,500 + Rs 126,380 + Rs 350,000 = Rs 563,880

Remaining amount = Rs 610,000 - Rs 563,880 = Rs 46,120

The money left with Chinmay is Rs 46,120.

Q18: Find the sum of the greatest and the least six digit numbers formed by the digits 2, 0, 4, 7, 6, 5 using each digit only once.

Ans: Sum of the Greatest and Least Six-Digit Numbers Formed by the Digits 2, 0, 4, 7, 6, 5:

Greatest number: 765420

Least number: 204567

Sum of greatest and least numbers = 765,420 + 204,567 = 969,987

The sum of the greatest and least six-digit numbers formed by the digits 2, 0, 4, 7, 6, and 5 is 969,987.