On the NY State Regents exam for Algebra, you only need to get half of the multiple-choice question right to pass, and not even bother with the 9 open-ended questions. This is make up for the fact that they asked some of the stupidest questions, and when you least expect it, ask several questions requiring depth of knowledge in minor Algebra topics that are usually glossed over because there’s over 100+ topics that need to be taught. That’s the curriculum for you: mile-wide, inches-deep.
I remember feeling exactly the same way when I took my regents in high school.