Class 6 Maths Chapter 1 Important Question Answers - Knowing Our Numbers

Q1: Write the numeration for 80956156  in the Indian system.

Ans: The numeration for 80956156 in the Indian system is, 8,09,56,156.
Eight crore nine lakh fifty-six thousand one hundred fifty-six.

Q2: Find the greatest and the smallest number:
42375, 42367, 42329, 42338.
Ans: The greatest number is 42375
The smallest number is 42329

Q3: Write the place value and face value of the underlined digit: 958465459

Ans: The place value and face value of the underlined digit: 958465459 is,
Place value of 8⇒8×1000000=8000000
$8\Rightarrow 8\times 1000000=8000000$
Face value of 8$8$ =8

Q4: Find the greatest number from below number:
763298 and 764298
Ans: 764298 is the greatest number

Q5: Kirti Bookstore sold books worth Rs.2,85,891 in the first week of June and books worth Rs.4,00,768 in the second week of the month. How much was the sale for the two weeks together? In which week was the sale greater and by how much?
Ans: Sale of books in the first week = Rs.2,85,891.
Sale of books in the second week = Rs.4,00,768
∴ Sale for the two weeks together = Rs.2,85,891 + Rs.4,00,768 = Rs.6,86,659.
The sale was greater in the second week by Rs. 4,00,768 – Rs.2,85,891 i.e., by Rs.1,14,877.

Q6: 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 millions four hundred twenty three thousand two hundred two.
Ans: (a) 73,75,307
(b) 9,05,00,041
(c) 7,52,21,302
(d) 58,423,202

Q7: How many crores make a billion?
Ans: 1 billion = 100 crore

Q8 Insert commas suitably and write the names according to the International System of Numeration: 78921092
Ans: 78,921,092

Q9: Starting from the smallest 8-digit number, write the next five numbers in ascending order.
Ans: The smallest 8-digit number is 1,00,00,000 and the next four numbers are 1,00,00,001, 1,00,00,002, 1,00,00,003 and 1,00,00,004

Q10: The capacity of a water tank is 300 litres. Express its capacity in millilitres.
Ans: We know that
1 litre = 1000 mL
∴ 300 litres = 300 x 1000 mL = 3,00,000 mL
Hence, the capacity of water tank = 3 lakh millilitres. 

Q11: What is the successor of greatest 6-digit number?
Ans: Greatest 6-digit number = 999999
Successor of it = 999999 + 1 = 1000000
i. e., smallest 7-digit number.
Hence, the required successor = 10,00,000.

Q12: A student multiplied 3759 by 231 instead of multiplying by 213. How much was his product greater than the correct product?
Ans:
First Method:
(3759 x 231)-(3759 x 213) = 868329 – 800667 = 67662
Second Method: 
3759 x (231 – 213) = 3759 x 18 = 67662
Hence, the product difference is 67662. 

Q13: The distance between the school and Reena’s house is 1 km 480 m. Everyday she walks both ways. What distance does she cover in 6 days of a week?
Ans:
Distance covered when she walks one way = 1 km 480 m = 1480 m
Therefore, the distance covered when she walk both ways in a day = 1480 x 2 m = 2960 m
Total distance covered by Reena in 6 days = 2960 x 6 m = 17760 m or 17 km 760 m. 

Q14: To stitch a pant 1 m 15 cm cloth is needed. Out of 36 m cloth, how many pants can be stitched and how much cloth will remain?
Ans:

Cloth required to stitch 1 pant = 1 m 15 cm
= 100 cm + 15 cm [∵ 1 m = 100 cm]
= 115 cm
Total cloth = 36 m = 36 x 100 cm = 3600 cm
Therefore number of pants stitched = 3600115
Hence, 31 pants can be stitched and cloth left over is 35 cm. 

Q15: There are two factories located at place P and the other at place Q. From these factories, a certain commodity is to be delivered to each of the depots situated at A, B and C. Weekly production of commodity by P and Q are 120 kg and 150 kg respectively. Weekly requirement of commodity by A, B and C are 80 kg, 90 kg and 100 kg respectively. P delivers 60 kg to A, 40 kg to B and 20 kg to C. How much amount of the commodity should Q deliver to A, B and C to meet their requirement? If the rate of the commodity is ? 20 per kg, find the total amount to be paid to P and Q.
Ans:

Amount of commodity delivered by P to A = 60 kg
Amount of commodity delivered by Q to A = 80 – 60 = 20 kg
Amount of commodity delivered by P to B = 40 kg
Amount of commodity delivered by Q to B – 90 – 40 = 50 kg
Amount of commodity delivered by P to C = 20
Amount of commodity delivered by Q to C = 100 – 20 = 80 kg.
Now Amount of money to be paid to P by A, B and C = ₹( 60 x 20 + 40 x 20 + 20 x 20)
= ₹ (1200 + 800 + 400)
= ₹ 2400
and amount of money to be paid to Q by A, B and C
= ₹ (20 x 20 + 50 x 20 + 80 x 20)
= ₹ (400 + 1000 + 1600) = ₹ 3000
Hence, the total amount
= ₹ 2400 + ₹ 3000 = ₹ 5400.