This is actually a pretty legit question.
It depends on how much fries or mcnuggets you want.
So I came up with this.
A Ten Piece Mcnuggets is $8.99
A large Fries is &1.79
So 8.99/7.79 = 5.0223463687150838
Or you can round that to 5.
So to answer your question, 5 Fries = 1 Ten Piece Mcnuggets.
Hope this answers your question! XD