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Class : 3

Subject: Maths

Week No:

Topic: Numbers

Periods No:


Make understand to children Roman and Indo- arabic numbers through fun.

Teaching Aids

Story and Drama, stones, countdown-3, worksheets


First I will tell a story of ancient. When people did not know how to write numbers they did not know any thing about math. They use to keep lots of cattle. The cattle go to jungle and when come back always find less cattle but how much less they have no idea. Then one wise man he started thinking how to know that how much cattle he lost? So he collected stones equal of cattle. When he reduce his cattle for grazing, he match each cattle with stone and kept separately. When cattle came back from jungle. He again match chattel with the stones. Whatever stone left he understood that he lost this much cattle. Then he developed that instead of stone he can make line on his wall. So he draw one line for one cattle. So roman number introduce from this line. This story will dramatizes by teacher. Few children will be cattle and few will be tigers. Teacher will be owner of the cattle. About two thousand year ago, the Romans developed a different system of numeration. They used seven letters of the alphabet as basic symbols to write any numbers! They are: I V X L C D M. These line known as Romans numbers later develop for examples after III they developed IV for 4 and V for 5, X for 10, L for 50, C for 100, D for 500 and M for 1000.

I will explain that there is no zero and place value in Roman no. Zero introduced by Ramanujan. And the Romans had no special symbols for the numerals 2,3,4,6,7,8,9.This meant that their numerals were rather long and difficult to write down.But they had very good system about their numbers.They used to follow rules

Rule 1: Numerals, I,X,C, and M can be repeated to represent a number. Repetition of these numerals means addition.

E.g. 11=2, XXX=30, MM=2000, CCC=3000

These symbols cannot be repeated more than 3 times in a numeral

e.g. 4 is written as IV, not IIII

Symbols, V,L,D are not repeated.

Rule 2: A smaller numeral written to the right of a numeral of greater value is always added to of greater numeral.

Example: XI=10+1=11 LX=50+10=60 VII=5+2+7

When a smaller numeral is placed between two numerals of greater value, it is always subtracted from of greater numeral immediately following it.

E.g. XXIX=10+10+(10-1)=29 XIV=10+(5-1)=14

The symbol I can be started from V and X

The symbol X can be subtracted from L and C.

The symbol C can be subtracted from D and M.

Symbols V,L,D are never subtracted.

Once children understand concepts of Romans numbers they will page no. 72 and 73 from countdown-3. Teacher will give more work on board where children can do addition and subtraction by using Romans numbers.

Reference countdown-3.
Homework Children will given worksheets for Romans numbers.

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