Skip to main content

2021 AMC 10B Problem 17

Problem 17 of 25Intermediate

Ravon, Oscar, Aditi, Tyrone, and Kim play a card game. Each person is given 22 cards out of a set of 1010 cards numbered 1,1, 2,2, 3,3, ,\dots, 10.10. The score of a player is the sum of the numbers of their cards. The scores of the players are as follows: Ravon--11,11, Oscar--4,4, Aditi--7,7, Tyrone--16,16, Kim--17.17. Which of the following statements is true?

Answer choices

Show solution

Solution

Oscar’s score of 44 forces his cards to be 11 and 3.3. From the remaining cards, the only pair with sum 77 is 22 and 5,5, so those are Aditi’s cards. The unused cards are now 4,6,7,8,9,10.4,6,7,8,9,10. Tyrone’s score of 1616 can come only from 6+106+10 or 7+9.7+9. If Tyrone had 77 and 9,9, then the remaining cards 4,6,8,104,6,8,10 could not be paired to give Ravon’s score 11.11. Thus Tyrone has 66 and 10.10. The remaining cards are 4,7,8,9.4,7,8,9. Ravon must have 44 and 77 to score 11,11, leaving 88 and 99 for Kim’s score of 17.17. Therefore, Ravon was given card 4.4. Thus, the answer is C .

More practice

Concepts: logical deduction

Problem text and solution from the LIVE past-contest archive. See also the AoPS wiki page for community solutions.