← Back to view Tip: choose "Save as PDF" as your printer for a clean PDF
Answer Key — Teacher Copy
Mathematics

Exploring Numbers and Numeration Systems Worksheet

Large Numbers, Numeration Systems, and Estimation
Date: May 31, 2026  •  40 questions  •  Total: 100 points
StudentAayush Nayak
Class6-B
GradeGrade 6
SchoolYBIS
1. True / False (1 pts)
The number 9999989 is less than 9999999.
✓ Answer
True
2. True / False (1 pts)
Adding 1 to the greatest 7-digit number results in an 8-digit number.
✓ Answer
True
3. True / False (1 pts)
The Indian and International systems of numeration use the same comma placements.
✓ Answer
False
4. True / False (1 pts)
Rounding off a number to the nearest hundreds always increases its value.
✓ Answer
False
5. True / False (1 pts)
The Roman numeral MCMXI represents the year 1911.
✓ Answer
True
6. True / False (1 pts)
The face value of a digit is always equal to its place value in the number.
✓ Answer
False
7. True / False (1 pts)
Zero acts as a placeholder in large numbers.
✓ Answer
True
8. True / False (1 pts)
Rounding off can sometimes lead to a result greater than the actual sum.
✓ Answer
True
9. True / False (1 pts)
The predecessor of the smallest 7-digit number, when added with 1, gives the smallest 7-digit number.
✓ Answer
True
10. True / False (1 pts)
Round-off estimation is not useful in everyday calculations.
✓ Answer
False
11. Multiple Choice (2 pts)
What is the smallest 7-digit number?
✓ Answer
A. 1000000
12. Multiple Choice (2 pts)
What is the greatest 7-digit number?
✓ Answer
A. 9999999
13. Multiple Choice (2 pts)
In the Indian numeral system, 1,00,00,000 is commonly known as:
✓ Answer
D. Both A and C
14. Multiple Choice (2 pts)
According to the chapter, what is the predecessor of 100000?
✓ Answer
A. 99999
15. Multiple Choice (2 pts)
What is the place value of 5 in 10506?
✓ Answer
C. 5000
16. Multiple Choice (2 pts)
Adding 1 to the greatest 7-digit number gives you the smallest _____-digit number.
✓ Answer
B. 8
17. Multiple Choice (2 pts)
In Roman numerals, the numeral IX represents:
✓ Answer
B. 9
18. Multiple Choice (2 pts)
Rounding 535674 to the nearest hundred results in:
✓ Answer
A. 535700
19. Multiple Choice (2 pts)
Which of the following best describes the process of estimating large numbers by rounding?
✓ Answer
B. Approximation
20. Multiple Choice (2 pts)
What does the process of converting a Roman numeral to its numeric form involve?
✓ Answer
C. Both addition and subtraction
21. Fill in the Blank (2 pts)
The number obtained by adding 1 to the greatest 7-digit number is _____.
✓ Answer
10000000
22. Fill in the Blank (2 pts)
The smallest 8-digit number is _____.
✓ Answer
10000000
23. Fill in the Blank (2 pts)
The smallest 9-digit number is _____.
✓ Answer
100000000
24. Fill in the Blank (2 pts)
In the Indian numbering system, 1,00,00,000 is called _____.
✓ Answer
one crore
25. Fill in the Blank (2 pts)
The place value of 5 in 10506 is _____.
✓ Answer
5000
26. Fill in the Blank (2 pts)
The Roman numeral for 1911 is _____.
✓ Answer
MCMXI
27. Fill in the Blank (2 pts)
In rounding off numbers, if the digit to the right is 5 or more, you round _____.
✓ Answer
up
28. Fill in the Blank (2 pts)
Writing numbers in _____ order helps in identifying the smallest and largest numbers.
✓ Answer
ascending
29. Fill in the Blank (2 pts)
Rounding 535674 to the nearest hundred gives _____.
✓ Answer
535700
30. Fill in the Blank (2 pts)
In the international numeral system, 1000000 is known as _____.
✓ Answer
one million
31. Word Problem (5 pts)
Add 7834567, 893600678, and 1035678. Show your working.
✎ Worked Solution
Step 1: Add 7834567 and 1035678 to get 8870245
Step 2: Add 8870245 and 893600678 to get 902470923
Answer: 902470923
32. Word Problem (5 pts)
Find the sum of the greatest 8-digit number and the smallest 5-digit number. Show your working.
✎ Worked Solution
Step 1: Identify numbers: 99999999 and 10000
Step 2: Sum = 99999999 + 10000
Answer: 100009999
33. Word Problem (5 pts)
Estimate the difference between 89567 and 34589 when both are rounded to the nearest hundreds. Show your working.
✎ Worked Solution
Step 1: Round 89567 to 89600 and 34589 to 34600
Step 2: Calculate difference: 89600 - 34600
Answer: 55000
34. Word Problem (5 pts)
A man travels from a hotel to Varkala beach 850 m away and returns. Calculate the total distance traveled in 10 days if he makes one round trip per day. Show your working.
✎ Worked Solution
Step 1: Calculate daily round trip: 850 x 2 = 1700 m
Step 2: Multiply by 10 days: 1700 x 10
Answer: 17000 m
35. Word Problem (5 pts)
A house priced at ₹32,56,358 increases by 20 times the next year. Find its new price. Show your working.
✎ Worked Solution
Step 1: Multiply ₹32,56,358 by 20
Step 2: 3256358 x 20 = 65127160
Answer: ₹65,127,160
36. Word Problem (5 pts)
A businessman invested ₹1,20,00,000 and earned a profit of ₹1,20,000. If he reinvests the profit, what is his total investment? Show your working.
✎ Worked Solution
Step 1: Identify investment: 12000000 and profit: 120000
Step 2: Total = 12000000 + 120000
Answer: 12120000
37. Word Problem (5 pts)
Vanaja completed a 1 km race in 96 seconds and Sunantha in 188 seconds. By how many seconds was Vanaja ahead? Show your working.
✎ Worked Solution
Step 1: Subtract Vanaja's time from Sunantha's time
Step 2: 188 - 96 = 92
Answer: 92 seconds
38. Word Problem (5 pts)
Roy rounded 3567 and 935 to the nearest hundreds and multiplied them. What is the estimated product? Show your working.
✎ Worked Solution
Step 1: Round 3567 to 3600 and 935 to 900
Step 2: Multiply rounded numbers: 3600 x 900
Answer: 3240000
39. Word Problem (5 pts)
Verify the place value calculation for the digit 5 in 21865734. Show your working.
✎ Worked Solution
Step 1: Identify digit 5 in number 21865734 (thousands place)
Step 2: Calculate place value: 5 x 1000 = 5000
Answer: 5000
40. Word Problem (5 pts)
Convert the Roman numeral 'MCMXI' to its numeric value. Show your working.
✎ Worked Solution
Step 1: Interpret M as 1000, CM as 900, and XI as 11
Step 2: Add values: 1000 + 900 + 11
Answer: 1911