Question

90 gifts were distributed in a party. Everyone presented a gift to another. How many persons were there in the party ?

• A. $9$
• B. $10$
• C. $81$
• D. $89$

Answer 1

Answer: (B)

$10$

If there will be 10 persons in party, 1 person will have 9 gifts so he can give 1 gift to each other person. Or in other words 1 person will give 9 gifts for another 9 persons.
If 1 person will give 9 gifts to another 9 persons
then 10 persons will give $10\times 9=90$ gifts to another 9 persons.
Thus "Option B" is correct answer.