Page 25 - ICSE Math 4

Rule 4: When three or more symbols are Mental Maths
wri en together in such a way that a smaller

Tick ( ) the correct option(s).
symbol lies between two larger symbols, then
(a) 37 = XXXVII (b) 26 = XXIV
we subtract the smaller symbol from the larger
(c) 25 = XXXV (d) 17 = XVII
symbol placed a er it.
Examples: XIV = 10 + (5 – 1) = 10 + 4 = 14, XIX = 10 + (10 – 1) = 10 + 9 = 19,

XXIV = 10 + 10 + (5 – 1) = 20 + 4 = 24, XXXIX = 10 + 10 + 10 + (10 – 1) = 30 + 9 = 39
Roman Numerals up to 39

Hindu- Hindu- Hindu- Hindu-
Roman Roman Roman Roman
Arabic Arabic Arabic Arabic
Numeral Numeral Numeral Numeral
Numeral Numeral Numeral Numeral

1 I 11 XI 21 XXI 31 XXXI

2 II 12 XII 22 XXII 32 XXXII

3 III 13 XIII 23 XXIII 33 XXXIII

4 IV 14 XIV 24 XXIV 34 XXXIV

5 V 15 XV 25 XXV 35 XXXV

6 VI 16 XVI 26 XXVI 36 XXXVI

7 VII 17 XVII 27 XXVII 37 XXXVII

8 VIII 18 XVIII 28 XXVIII 38 XXXVIII

9 IX 19 XIX 29 XXIX 39 XXXIX

10 X 20 XX 30 XXX

Exercise

1. Complete the given table.

Hindu-Arabic Numeral Roman Numbers
(a) 38 ______
(b) ______ XXIX

(c) 24 ______

(d) ______ XXXVI

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