When applying two-value boundary value analysis for grading conditions, how many test cases are required for coverage?

In boundary value analysis, the focus is on values at the boundaries of input ranges, as errors are often found at these extremes. For two-value boundary value analysis, it is crucial to consider both the limits and the values just outside those limits.

When grading conditions, specifically looking at a grading scale (for instance, a score required to pass), you often have defined boundaries. If we assume that there are different thresholds (such as 0 to 100 points), boundary value analysis would require testing at the minimum and maximum points as well as just below and just above those thresholds.

For instance, if we have defined grades at certain points (say, thresholds like 50, 60, 70, etc.), the test cases would include both the critical boundary values and the values immediately surrounding them. This ensures that edge cases are verified, and all potential transition points between different grades are tested.

If we analyze a grading system that has multiple thresholds, a comprehensive test case set could potentially include:

• Values just below and just above each threshold,
• The boundary values themselves.

For each boundary grade, you would test:

• Just below the threshold (e.g. 49, 59, 69),
• The threshold itself (e.g.