Numbers that sit at a higher level

Have you seen 23, 35 and so on? Why are 3 and 5 sitting at a different level?

It is just mathematicians’ shorthand: 23 is nothing but 2 x 2 x 2 =  8

35 means 3 x 3 x 3 x 3 x 3 = 243

We read 23 as 2 to the power 3, and 35 as 3 to the power five.

What is 25 ?  Write it down.

What is 23 x 25 ?  One surprising thing is that 23 x 25 = 28 = 256

Numbers sitting one level higher are called exponents.

The exponent notation makes it very easy to write some big numbers. Try writing a million, billion and trillion! But with exponent notation, it is much easier to write them and remember them.

Number

In decimal notation

In exponent notation

Million

1,000,000

106

Billion

1,000,000,000

109

Trillion

1,000,000,000,000

1012





Did you notice it? Million has six zero’s and is 106; billion has nine zero’s and is 109; trillion has twelve zero’s and is 1012.

Srinivasan Ramani

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