you could also use regular expressions to represent your string. The regular expression below says to look for the string "RS", followed by a decimal characters (.), followed by zero or more numeric digits followed by zero or more decimal characters, followed by zero or more digits. The parentheses enclose the part of the regular expression that you want to keep (it stores it in Matches(0).SubMatches(0) in this example). The resulting string is everything but "RS" at the beginning of the string and the trailing "/-" string.
Code:
Dim regEx, Matches, returnString ' Create variable.
Set regEx = New RegExp ' Create a regular expression.
regEx.Pattern = "RS\.*(\d+\.*\d*)/-" ' Set pattern
regEx.IgnoreCase = True ' Set case insensitivity.
regEx.Global = True ' Set global applicability.
strng="Rs.4500.00/-"
'strng="RS340067.23/-"
Set Matches = regEx.Execute(strng) ' Execute search.
If Matches.Count=1 Then
If Matches(0).SubMatches.count=1 Then
End If
returnString=Matches(0).Submatches(0)
End If
msgbox returnString
set regEx=nothing