For finding grade boundaries, a general approach to the normal distribution is followed. And according to famous mathematician Layman, bell curves refer to the normal distribution process.

As there is quite a dilemma between the bell curves, it must mention here, that officially it has been declared that no bell curve approach is being followed for any O level exams. Instead of that, the student's results are published, and the normal distribution approach is applied after that.

Consequently, saying bell curves do not exist is also not true either. The accurate thing is bell curve might work but after the scores of the total students are considered.

How Bell Curve Works?

The bell curve looks like the bell in total. The highest point of the curve means that most of the data is scattered here. No doubt, this is the spot where the mean, mode, and median are located.

In every bell curve, this is the most obvious point where the scores of 75 to 90 are located (that means the grades from B to A). Above this section refers to A* and below this refers to C grade.

Other than that, the symmetrically distributed area is the mean of the scores. The peak above and below is known as the standard deviation.

However, bell curves are used for depicting both normal distribution and non-normal distribution curves. As a result, thinking the bell curves are only used in the grading system is a major folly.

The more accurate version is the bell curve that depicts the normal distribution of the scores of the total students is what O level subjects require.

In terms of the bell curves, different subjects have different approximate points in the mean, mode, and median. No two subjects can have the same value. Yet, if happens, this is a rare scenario.

In Singapore, bell curves are hugely considered as the benchmark of each subject. As a result, students are confused as well as curious to know the approximate bell curve point to compare with themselves.

In chemistry, the approximate bell curve value is 83. Despite being unfavorable to many of the subjects, chemistry tends to have the sweet spot for the students. And the pressure and tension are also eased.

Additionally, papers on chemistry hardly trick the student. For this reason, a greater bell curve approximation is expected. Still, the lower value enables greater A and A* grades for the prospective students.