Place Value in Daily Life

< 6.2 Number Systems 2 | Topic Index | 6.4 Place Value System >

Children find it difficult to relate to the place value system in mathematics for 2 reasons.

One is that the idea is something they have never experienced in life before.

Second is that this abstract idea is taught to them using several similar &amp; confusing terms. They are not able to differentiate between the different terms &ldquo;one&rdquo;, &ldquo;one&rsquo;s&rdquo;, &ldquo;ten&rdquo; &amp;&rdquo; ten&rsquo;s&rdquo; and the idea of a &ldquo;place&rdquo;.

It would be better if children are first familiarised with the idea of place value, as it occurs in daily life but which has never been perceived as a place value system. Let us take examples from Postal System and Date System. (Unfortunately, with the invention of email &amp; sms, even the idea of a postal system may become alien!)

Imagine you are a postman and that you have to deliver a letter whose address is written in the manner shown as &ldquo;Address A&rdquo;.

Most likely you will interpret that the letter has to be delivered to Anuradha living in a house called Lakshmi. However, if the address is written as given in &ldquo;Address B&rdquo;, then it would be delivered to Lakshmi living in a house called Anuradha.

Hence the postal system has a (unwritten) place value system where the first line has the value &ldquo;Name of the Person&rdquo; and the second line has the value &ldquo;Name of the House&rdquo;. The way &ldquo;Anuradha&rdquo; is interpreted depends on place where it occurs in the address. We can say that the value of &ldquo;Anuradha&rdquo; depends on its place, relative to the rest of the address.

Let us now look at how dates are written in different countries. 11thSeptember is written a 9/11 in the US and 11/9 in India. In India we write a date in the dd/mm/yyyy format, whereas in the US it is written in the mm/dd/yyyy format. The value of a number in a date sequence depends on its position or place in the date which again is dependent on the convention adopted by a country. To be able to operate effectively in a new situation (or country in this context) we need to be familiar with its conventions including the place value systems. Unlike the postal place value, the date place value is formal and documented.

One medieval Indian mathematician has explained the idea of the place value system using the example of the same person being referred to by different names. He says that the same lady is sometimes referred to as &ldquo;mother&rdquo; and in other times variously as &ldquo;wife&rdquo;, &ldquo;sister&rdquo;, &ldquo;mami&rdquo; etc depending on a particular role that she is playing!

In the same way, in the Number Place Value System, the value of a number (or strictly numeral) depends on where it is written. To give quick example, the value of 2 in 24 is actually twenty and the value of 2 in 42 is two.

To understand the value of a number (as twenty-four or forty-two in the above examples) in our number place value system, we need to be conversant with the (decimal) place value system which is internationally used in mathematics today.

< 6.2 Number Systems 2 | Topic Index | 6.4 Place Value System >