Answer:
36
Explanation:
Total students un the contest = 84
Number of students who gave their speech yesterday:-
so 21 students gave their speech yesterday
- remaining students = 84 - 21
= 63
Number of students who gave their speech today:-
Number of students who have given their speech:-
= 21 + 27
= 48
Number of students who still haven't given their speech :-
= total - 48
= 84 - 48
= 36