Well, you tricked me.  (Though I could plug all this into my calculator and literally figure out the answer.)  I never knew that this had a name.  Then again, it was only 10 years ago when my 5th grade teacher played this exact same prank on me.
I wouldn't say it's a reading comprehension test, but rather a "Following the rules test."  Most children dive right into following all of the things set out that they forget to read the introduction to the test.  They don't realize (as I didn't) that there is more to every test then the questions.