Numbers that sit at a higher level
Have you seen 2 3 , 3 5 and so on? Why are 3 and 5 sitting at a different level? It is just mathematicians’ shorthand: 2 3 is nothing but 2 x 2 x 2 = 8 3 5 means 3 x 3 x 3 x 3 x 3 = 243 We read 2 3 as 2 to the power 3, and 3 5 as 3 to the power five. What is 2 5 ? Write it down. What is 2 3 x 2 5 ? One surprising thing is that 2 3 x 2 5 = 2 8 = 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 10 6 Billion 1,000,000,000 10 9 Trillion 1,000,000,000,000 10 12 Did you notice it? Million has six zero’s and is 10 6; billion has nine zero’s and is 10 9 ; trillion has twelve zer