TIMO THPT – Vòng Quốc gia (Heat Round) – Đề số 1

Selena's dessert is stolen. She asked her 4 guests and got replies as follows: • Hera: "David's stolen it." • David: "Hera's stolen it." • Ruby: "I have not stolen it." • Steve: "David is lying." Given that only one of them had told the truth, who stole Selena's dessert?

Dessert: Món tráng miệng; Lie: Nói dối; Tell the truth: Nói thật.

If x, y and z are all prime and 4 y x x y z + = , find the minimum value of z.

Prime: Số nguyên tố; Minimum value: Giá trị nhỏ nhất.

Divide a rectangle into 3  identical small squares, and paint each small square in either red or green. How many ways to paint them so that there doesn't exist a rectangle with area not less than four that has four cell at corners painted in same color?

tích;

Divide: Chia; Rectangle: Hình chữ nhật; Identical: Giống nhau; Square: Hình vuông; Area: Diện

Less than: Ít hơn

Corner: Góc

Same: Giống nhau