Determining the Least Common Multiple

One way "to make sure you are working with actual integers with LCM" if you do have decimal numbers, is to convert the them to integers first. Let's say your numbers go to two decimal places. The formula to get their LCM would be:

=LCM(C20:C23*100)/100

If yours numbers go to three decimal places, then the 100's would need to be changed to 1000's, and so on. A more generic version (for up to 6 decimal places) might be:

=LCM(C20:C23*1000000)/1000000

Hmm, It is a pity that there is now editing function here. Someone else has also made this comment ealier.

The first Pic is

(see Figure 1 below)

For something to do while stuck in the house I thought I'd try remembering how the HCF and HCD (GCD) worked.
The HFC is got by muliplying all the values and dividing the answer by the smallest value. A couple of functions are available, the PRODUCT and MIN functions. I also put these functions into a UDF as follows:

Function myLCM(ByVal ref)
Dim myMin As Long, myProd As Long
myProd = Evaluate("product(" & ref.Address & ")")
myMin = Evaluate("Min(" & ref.Address & ")")
myLCM = myProd / myMin
End Function

(see Figure 1 below)
The HCD (GCD) requires two loops, not shown in pic2. an outer loop For i = 1 to ref.count and an inner loop, Do ....Until a = 0. Here it is:

Function myHCD(ByVal ref)
Dim i As Long
Dim a, b, c

For i = 1 To ref.Count - 1
If IsEmpty(ref(i)) Then
i = i + 1
End If
If ref(i) > ref(i + 1) Then
a = ref(i): b = ref(i + 1)
Else: a = ref(i + 1): b = ref(i)
End If

Do
c = a Mod b
a = b
b = c
Loop Until b = 0

Next i
myHCD = a
End Function

(see Figure 2 below)

John,
The HCF is called GCD (Greatest Common Denominator). Separated by a common language?

I Just noticed this tip. It took me back a very long way to my school days (I'm now 78), I don't remember the procedure any more, but I do remember that was one of the topics.

Along with LCM calculations, we were also taught the procedure for HCF calculations (Highest Common Multiple). So I immediately went and looked for that function in Excel 2010 - no joy.

As a matter of interest, got the same result for Open Office 4.14 - the LCM function worked, but no HCF function. I also tried the last version of Lotus 1-2-3. Neither function appeared to exist, but I couldn't check the help files since they won't run in Windows 10