Is LearnSmart final exam harder than the actual exam?

in Security+
I'm a bit concerned about how prepared I am for this exam. On the practice tests on Darril's book I got over 90%. Another book I got 88%. On the LearnSmart final exam I got a 76%. Anyone with experience with these practice tests and the actual exam have any insight on which practice tests are closer to the difficulty level of the actual exam?
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Also, many successful test takers talk about using this strategy and finding that it helps them eliminate incorrect answers especially when they come across questions that seem overly vague or confusing.
Hope this helps.
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Also, when I compare the actual exam to the LearnSmart practice test..... they are not even close. LearnSmart's questions focused on the wrong concepts and were so particular in it's terminology that I'd say it in no way tells you if you are ready for the real exam. If you use one tool to learn the concepts use Darril's book.