I need any equation to solve the required operation I am trying to create a calculator.
A=low       B=low             C=low
A=low       B=high           C=high
A=high      B=low             C=low
A=high      B=high            C=very-high  
Update
I am trying to create a calculator.
where A is the no.of attempts B is the score.I need a grading based on these factors ie C. when no.of attempts and score is high, it should be the only case where Grade must be high, remaining all cases grade should be low.
Example
Attempts = 5
Score = 4
Grade should be low as attempts and score is low
Attempts = 20
Score = 16
Grade should be VERY-HIGH as both score and attempts is high.
In the above examples both the ratios are equal but i need a higher weight-age for second case
Attempts = 5
Score = 50 
Grade should be HIGH as attempts is less
Attempts = 50
Score = 15
Grade should be less as score is less
How can i solve this.I need to confine the grade in between 1 and 10
 A: Then the answer is $C = A \land B$, or whatever symbol you use for conjunction (the 'and' operator, maybe $C=A B$).
A: Based on my understanding I have generated this sample:

I am assuming a max. value of 100 for A and S.
If this is what you want, the formulas are as follows:
$$R=(A*S)/(100*100)$$
This resulting values have min. value of $0$ and max. of $1$. You could scale this between $1$ and $10$ to get $S$ as follows:
$$S= ((10-1)*(R-Min)/(Max-Min))+Min$$ 
$$S= ((10-1)*(R-0)/(1-0))+1$$
Note: the division by 100*100 is not really required. You could omit it and change $S$ to be:
$$S= ((10-1)*(R-0)/(100*100-0))+1$$
Edit

As per the new requirement expressed in the note, here is a sample of the modefied formulas:
$$ R=(A*S) * (S/(A+10))$$
Here the value $A*S$ is multiplied by a factor that decreases the total value as A increases to cover the case for the new requirements.
The value of $10$ in the above expression is any value greater than zero so that when $A=0$ you don't get an error.
The max. value of R is when $A=100$ and $S=100$, at these points R=9090.91
$$ S==10*R/9090.91$$
Note that while the above formulas may produce correct numerical values, the may not be suitable to score exams and such because they may not represent fair marking (that requires statistics I don't know).
