Ten students are to be selected for a project from a class of 30 students.
Case I:
If 4 students join the project, then from remaining 26 students, rest of the 6 students are to be selected
Which can be done in 26C6
= 230230 ways
Case II:
If 4 students does not join the project, then from remaining 26 students, all the 10 students are to be selected.
Which can be done in 26C10
= 5311735 ways.
∴ Required number of selections = 26C6 + 26C10
= 230230 + 5311735
= 5541965