## Class 6 Maths Chapter 1 Knowing Our Numbers

**Exercise -1.1**

**1. Fill in the blanks:**

**(1) 1 lakh =________ ten thousand.**

**Answer:** 10: 1 lakh = 1,00,000

= 10 x 10,000 = 10 ten thousand

**(2) 1 million=_______ hundred thousand.**

**Answer:** 10:1 million = 1,000,000

= 10 x 100,000 = 10 hundred thousand

**(3) 1 crore =__________ ten lakh.**

**Answer:** 10: 1 crore = 1,00,00,000

= 10 x 10,00,000 = 10 ten lakh

**(4) 1 crore =__________ million.**

**Answer:** 10: 1 crore = 10 million

**(5) 1 million =_________lakh.**

**Answer:** 10: 1 million = 10 lakh

**2. Place commas correctly and write the numerals:**

**(1) Seventy three lakh seventy five thousand three hundred seven.**

**Answer:** 73,75,307

**(2) Nine crore five lakh forty one.**

**Answer:** 9,05,00,041

**(3) Seven crore fifty two lakh twenty one thousand three hundred two.**

**Answer:** 7,52,21,302

**(4) Fifty eight million four hundred twenty three thousand two hundred two.**

**Answer:** 58,423,202

**(5) Twenty three lakh thirty thousand ten.**

**Answer:** 23,30,010

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

**(1) 87595762**

**Answer:** 8,75,95,762 -> Eight crore seventy five lakh ninety-five thousand seven hundred sixty-two

**(2) 8546283**

**Answer:** 85,46,283 -> Eighty-five lakh forty-six thousand two hundred eighty-three.

**(3) 99900046**

**Answer:** 9,99,00,046 -> Nine crore ninety-nine lakh forty-six

**(4) 98432701**

**Answer:** 9,84,32,701 -» Nine crore eighty-four lakh thirty-two thousand seven hundred one.

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

**(1) 78921092**

**Answer:** 78,921,092 -> Seventy-eight million nine hundred twenty-one thousand ninetytwo

**(2) 7452283**

**Answer:** 7,452,283 —> Seven million four hundred fifty-two thousand two hundred eighty three

**(3) 99985102**

**Answer:** 99,985,102 —> Ninety-nine million nine hundred eighty-five thousand one hundred two

**(4) 48049831**

**Answer:** 48,049,831 —> Forty-eight million fortynine thousand eight hundred thirty-one

**Exercise – 1.2**

**1. A book exhibition was held for four days in a school. The number of tickets sold at the counter on the first, second, third and final day was respectively 1094, 1812, 2050 and 2751. Find the total number of tickets sold on all the four days.**

**Solution:** Number of tickets sold on first day = 1,094

Number of tickets sold on second day = 1,812

Number of tickets sold on third day = 2,050

Number of tickets sold on fourth day = 2,751

Total tickets sold = 1,094 + 1,812 + 2,050 + 2,751 = 7,707

Therefore, 7,707 tickets were sold on all the four days.

**2. Shekhar is a famous cricket player. He has so far scored 6980 runs in test matches. He wishes to complete 10,000 runs. How many ****more runs does he need?**

**Solution:** Number of runs to achieve = 10,000

Number of runs scored = 6,980

Number of runs required = 10,000- 6,980 = 3,020

Therefore, Shekhar needs 3,020 more runs.

**2. Shekhar is a famous cricket player. He has so far scored 6980 runs in test matches. He wishes to complete 10,000 runs. How many ****more runs does he need?**

**Solution:** Number of runs to achieve = 10,000

Number of runs scored = 6,980

Number of runs required = 10,000- 6,980 = 3,020

Therefore, Shekhar needs 3,020 more runs.

**3. In an election, the successful candidate registered 5,77,500 votes and his nearest rival secured 3,48,700 votes. By what margin did ****the successful candidate win the election?**

**Solution:** Number of votes secured by successful candidate = 5,77,500

Number of votes secured by his nearest rival = 3,48,700

Margin between them = 5,77,500- 3,48,700 = 2,28,800

Therefore, the successful candidate won by a margin of 2,28,800 votes.

**4. Kirti bookstore sold books worth 2,85,891 in the first week of June and books worth 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?**

**Solution:** Worth of books sold in first week = 2,85,891

Worth of books sold in second week = 4,00,768

Total worth of books sold = (2,85,891 +4,00,768) = 6,86,659

Since, 4,00,768 > 2,85,891

Therefore, sale of second week is greater than that of first week by (4,00,768- 2,85,891) = 1,14,877

**5. Find the difference between the greatest and ****the least 5 – digit number that can be written ****using the digits 6, 2, 7, 4, 3 each only once**

**Solution:** Greatest five-digit number using digits 6,2,7,4,3 = 76432

Smallest five-digit number using digits 6,2,7,4,3 – 23467

Difference = 76432- 23467 52965

Therefore, the difference is 52,965.

**6. A machine, on an average, manufactures 2,825 screws a day. How many screws did it produce in the month of January 2006?**

**Solution:** Number of screws manufactured in one day = 2,825

Number of screws manufactured in the month of January (31 days) = 2,825 x 31 = 87,575

Therefore, the machine produced 87,575 screws in the month of January.

**7. A merchant had 78,592 with her. She placed ****an order for purchasing 40 radio sets at 1200 ****each. How much money will remain with her ****after the purchase?**

**Solution:** Cost of one radio set = 1200

Cost of 40 radio sets = (1200 x 40) = 48,000

Now, total money with merchant = 78,592

Money left with her =(78,592- 48,000) = 30,592

Therefore,30,592 will remain with her after the purchase

**8. A student multiplied 7236 by 65 instead ****of multiplying by 56. By how much was his ****answer greater than the correct answer? (Hint: ****Do you need to do both the multiplications?)**

**Solution:**

Difference in answers = 470340- 405216 = 65,124

**9. To stitch a shirt, 2 m 1 5 cm cloth is needed. Out of 40 m cloth, how many shirts can be stitched and how much cloth will remain? ****(Hint: convert data in cm.)**

**Solution:** Cloth required to stitch one shirt = 2 m 15 cm = 2 x 100 cm + 15 cm = 215 cm

Length of cloth = 40 m = 40 * 100 cm = 4000 cm

Number of shirts can be stitched = 4000 / 215

Therefore, 18 shirts can be stitched and 130 cm (1 m 30 cm) cloth will remain.

**10. Medicine is packed in boxes, each weighing 4 kg 500 g. How many such boxes can be loaded in a van which cannot carry beyond**

**800 kg? **

**Solution:** The weight of one box = 4 kg 500 g

= 4 x 1000 g + 500 g = 4500 g

Maximum load can be loaded in a van = 800 kg = 800 x 1000 g = 800000 g

Number of boxes = 800000 ÷ 4500

Therefore, 177 boxes can be loaded in the van.

**11. The distance between the school and a ****student’s house is 1 km 875 m. Everyday ****she walks both ways. Find the total distance ****covered by her in six days.**

**Solution:** Distance between the school and house = 1 km 875 m = 1 km + 875/1000km=1.875km

Total distance covered in one day = (1.875 x 2)km = 3.750 km

Distance covered in six days = (3.750 x 6) km = 22.500 km

Therefore, a student covered 22 km 500 m distance in six days.

**12. A vessel has 4 litres and 500 ml of curd. In how ****many glasses, each of 25 ml capacity, can it be ****filled?**

**Solution: ** Quantity of curd in a vessel = 4 litres 500 ml = 4×1000 ml + 500 ml = 4500 ml

Capacity of one glass = 25 ml

Number of glasses can be filled = 4500 ÷ 25

Therefore, 180 glasses can be filled by curd