The next step is to design additional test cases to cover the 11 boundary conditions. One approach is to merge these conditions into the existing test cases (i.e., by modifying test case 4 in Figure 5.5), but this is not recommended because doing so could inadvertently upset the complete multicondition coverage of the existing test cases. Hence, the safest approach is to add test cases to those of Figure 5.5. In doing this, the goal is to design the smallest number of test cases necessary to cover the boundary conditions. The three test cases in Figure 5.6 accomplish this.