164.38 = (1 x 100) + (6 x 10) + (4 x 1) + (3/10) + (8/100)
Expanded form of 164.38
[tex]164.38=1 \times 10^2+6 \times 10^1+4 \times 10^{0}+3 \times 10^{-1}+8 \times 10^{-2}[/tex]
General Rule
[tex]ABCD.EFGH=A \times 10^3+B \times 10^2+C \times 10^1 +D \times 10^0+E \times 10^{-1}+F \times 10^{-2}+G \times 10^{-3} +D \times 10^{-4}[/tex]