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\\February 16, 2024 1:27 PM Surender Prajapati Proof 5 Reader _________________________ Date: ___________________74

Practice time 1e

1. round off each of the following numbers to the nearest 10.
(a) 75 (b) 247 (c) 865 (d) 4242

(e) 6052 (f) 8873 (g) 68744 (h) 508379

2. round off each of the following numbers to the nearest 100.
(a) 414 (b) 584 (c) 7650 (d) 8899

(e) 17209 (f) 28769 (g) 120111 (h) 318574

3. round off each of the following numbers to the nearest 1000.
(a) 9373 (b) 8720 (c) 107898 (d) 36509

(e) 218942 (f) 58975 (g) 1035609 (h) 2867366
4. round off each of the following numbers to the nearest: i. 10, ii. 100, iii. 1000.

(a) 52670 (b) 37645 (c) 25893 (d) 41982

(e) 547125 (f) 258356 (g) 362780 (h) 1670248

roman numeraLs

In Roman numerals, seven symbols are used to represent numbers. These symbols and
their corresponding Hindu-Arabic numerals are given below.

roman numeral I V X L C d M

Hindu-Arabic numeral 1 5 10 50 100 500 1000

rules for writing roman numerals

rule 1: Repetition of a Roman numeral means addition.
Remember
examples: (a) III = 1 + 1 + 1 = 3
Š I, X, C and M can be repeated
(b) XXX = 10 + 10 + 10 = 30 only thrice.
(c) CC = 100 + 100 = 200 Š V, L and D cannot be repeated.
Š I can be subtracted only from
rule 2: A smaller Roman numeral on the right side of V and X.
a larger Roman numeral is always added to the Š X can be subtracted only from
L and C.
larger Roman numeral. Š C can be subtracted only from

examples: (a) XIII = 10 + 1 + 1 + 1 = 13 D and M.
Š V, L and D are never
(b) XXV = 10 + 10 + 5 = 25 subtracted.

(c) CXX = 100 + 10 + 10 = 120
(d) DLX = 500 + 50 + 10 = 560 Note

(e) MCCX = 1000 + 100 + 100 + 10 = 1210 There is no symbol for zero
in the Roman number system.

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