2025 AMC 8
Complete problem set with solutions and individual problem pages
Problem 6 Easy
Sekou writes the numbers After he erases one of his numbers, the sum of the remaining four numbers is a multiple of Which number did he erase?
- A.
- B.
- C.
- D.
- E.
Answer:C
Solution 1
The sum of all five numbers is . Since is more than a multiple of , the number being subtracted must be more than a multiple of . Thus, the answer is .
Solution 2
The sum of the residues of these numbers modulo is . Hence, the number being subtracted must be congruent to modulo . The only such answer is .
Think Academy Powered by ChatGPT