Cycloalkane Naming Question

I was doing some revision when I came across this compound which was named:

3-butyl-1,1-dimethyl-5-propylcyclohexan…

Now, I was wondering why the following would be incorrect

5-butyl-1,1-dimethyl-3-propylcyclohexan…

Both of them have the same sum i.e. 10. Would the second be correct as well? Or is there some rule (which I haven't been able to find yet) which has to be applied. Some more examples of these are:

1,3-diethyl-5,7-dimethylcyclononane (correct)
5,7-diethyl-1,3-dimethylcyclononane (incorrect?)

1-ethyl-3-methyl-2-propylcyclopentane (correct)
3-ethyl-1-methyl-2-propylcyclopentane (incorrect?)

Thanks in advance.

When an alkyl is branched on the main chain, you have to give priority to:
1) the lowest sum of rank numbers
2) the number of branched alkyls: that's why in the first example you would rank first the two methyls
3) the number of carbons of the alkyl: that's why in the first example you would rank the butyl (C4) before the propyl (C3)

So example 1:
--> dimethyl > butyl > propyl

Example 2 (same rules):
diethyl (2xC2) > dimethyl (2xC1)

Example 3:
Same thing : for a sum of 6, you can't rank the propyl first, but between ethyl and methyl you have to rank the ethyl first so ethyl > propyl > methyl

The rules are the same than the acyclic hydrocarbons' rules. You can find them here:
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