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.