At a math circle meeting, 10 students met. If every student shook hands with every other student exactly once, how many handshakes were there in total?
The MetaShkola website (Russian language) provides past problems and solutions. metashkola olimpiada po matematike zadaniia
A three-digit number is divisible by 9. If you swap the first and last digits, the new number is also divisible by 9. How many such numbers exist where the middle digit is 5? Part 3: Geometry & Spatial Thinking (15 points each) At a math circle meeting, 10 students met
A square piece of paper is folded in half twice to form a smaller square. A corner of this small square is cut off. When the paper is unfolded, how many holes will there be, and what shape will they form? A three-digit number is divisible by 9
What is the next number in the pattern? Explain the rule used.