(Q). In the annual function of a school every student gave a gift to every other student. If total number of gift distributed is 380 then
(i). How many students were present in the function?
(ii). How many gifts received by a particular student Amit ?
Solution:-
Let there are total n students in school.
2 students can be selected in ⁿC₂ ways
& since every student gave gift to every other student
Hence total number off gifts distributed = 2×ⁿC₂ = 380
⟹ 2 × = 380
n(n-1) = 380
∴ n = 20
Hence (i). 20 students were present in the function Answer
(ii)
A particular student Amit will receive gift from remaining all students except Amit = 19 Answer
