Percentages can be confusing. When dealing with percentages you should always ask yourself "Percentage of what?"
In your situation you have a group of owners who together own 66% of some property and one owner who owns 34% of this property. I don't know what this property is but I am going to say there are 100 property units in total. Thus the group owns 66 property units and the individual owns 34 units. You need to transfer 16 units from the group to the individual. These 16 units are 16% of the total 100 units not 16% of the 66 units owned by the group. 16% of 66 is 16/100 66 = 10.56 and hence by taking 16% from each owner in the group you were only transferring 10.56 units.
If you want to transfer the same percentage of each owners holdings to the individual you need to ask "What percentage of 66 units is 16 units?" That is what is x if
x/100 66 = 16
x = (16 100)/66 = 24.24
Hence you need to transfer 24.24% of the holdings of each member of the group to the individual owner.