Page 19 - Maths Class 04

2. Round these numbers to the nearest 100.

a. 7293 b. 8148 c. 95 d. 57669

3. Round these numbers to the nearest 1000.

a. 7500 b. 68199 c. 7095 d. 763521

4. Estimate to find out the numbers.

a. They are whole numbers that round to 10000 when rounded off to the

nearest thousand. What numbers are they ?

b. We are whole numbers that are rounded off to 80000 when rounded to
the nearest thousand. What numbers are we ?

Roman Numerals

Numbers are written in many ways, but the Hindu-Arabic number system

and Roman number system are the most commonly used.

In the Hindu-Arabic number system, we use ten digits for writing numbers.

These digits are— 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9.

The Roman numeral system has seven symbols— I, V, X, L, C, D and M.

Bigger numbers are formed by the combination of these symbols on the

basis of some special rules.
1 I
Rule I : Putting a smaller numeral on the right of
5 V
a greater numeral, means we add both of
10 X
them. The sum represents the number.
50 L
a. 6 = VI (5 + 1) 100 C

b. 15 = XV (10 + 5) 500 D

c. 18 = XVIII (10 + 5 + 3) 1000 M

Rule II : Putting a smaller numeral on the left of a greater numeral, means
we subtract the smaller one from the greater numeral. The difference

represents the number.

a. 4 = IV (5 – 1)

b. 9 = IX (10 – 1)

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