The Story:
Today, the Maths quizzes are handed out by the teacher.
You got 100/100. Everyone got 100/100.
But you're not happy with it. Everyone's not happy with it.
You want to score lower. Everyone wants to score lower.
What? Why? Yes, that's the truth.
So, one of your classmates, proposed an idea. You are all going to compete for the lowest mark.
But, everyone knows each other's mark.
So, why the challenge? Because... everyone has a chance (or more)
The challenge: The teacher sees that you are all unsatisfied, and decided to give you all one more chance. This would be your final result.
The Quiz:
The Maths teacher is queer. The quiz consists of only one question scoring 100% of the quiz.
The Question:
Use $1,2,3,4,5,6,7,8,9$ to form $100$, each digit once and only once.
Criteria:
For each use of a new kind of operator, $+10$ marks.
For each concatenation of digits, $+5$ marks.
For each operator:
Count the use of that operator. Let that be $n$. $-n(n-1)/2$ marks.
If the Maths teacher find any unnecessary operators, +50 for each one.
Can you win the challenge? What's your score?
List of allowed operators:
$+, -, *, /$ [as in division]$, \sqrt{} , \text{^}$ (as in exponentiation), $floor(), ceil()$
List of operators not allowed:
$!, \log()$
For any inquiries about operators, feel free to ask in the comments. Happy Puzzling ;)
Sorry for the horrible explanation by the Maths teacher. There was a mess during the requiz. Here is a dialogue:
JonMark Perry: Do we have to use every digit 1-9 exactly once?
Teacher: Yes.
Thomas Blue: Do we actually have to compete? I mean, wouldn't $123456789 = 100$ give us the lowest score, since it will also be wrong?
Teacher: Yes. The equation needs to be valid.
Athin: What is unnecessary operators?
Teacher: operators that can be directly removed without changing the result. Sorry for all this chaos as this is the first time I created such a puzzle...
Teacher: Puzzles belong to the intelligent, and those who find loopholes always have the wit to win... Perhaps the teacher should become the student and the student the teacher... [sigh]...
Hope this helps!