IS or ARE, when do you use one or the other? [duplicate]

Solution 1:

It depends on the item/items to which the percentage refers. When discussing something numerable, such as "10% of commenters," the plural would be appropriate. If something innumerable, such as "10% of the solution," then you would use the singular.

Solution 2:

It depends on if the percentage is made up of units (e.g. 10% of people) or is part of a whole (e.g. 10% of the cake).

If it's made up of units, then use the plural:

Of the top 100 earners, 10% own a yacht.

If it's part of a whole, use singular

I made the pie, so 10% is mine.

In the case of a percentage of units, of them is being erased. In the case of a whole of it is being erased.