TIMO Khối 8 – Vòng Quốc gia (Heat Round) – Đề số 1

Selena's dessert is stolen, she asked her 4 guests and received replies as the followings: Hera: "David's stolen it." David: "Steve'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?

Lying: Nói dối; Told the truth: Nói thật.

Split 85, 104, 119, 121, 143, 161, 176 and 230 into 2 groups of 4 numbers such that the products of numbers in both groups are equal. Find the sum of the numbers of the group that contains 104.

Split: Tách; Groups: Nhóm; Products: Tích; Equal: Bằng nhau; Sum: Tổng.

John wrote a 4-digit number on a paper and asked Peter to guess it. Peter asked: "Is the number 4321?" John replied: "Three digits are correct. The positions of those digits are also correct." Peter asked again: "Is the number 2420?" John replied: "Two digits are correct, but the positions of those digits are both wrong." What is the number written by John? 4-digit number:

Số có 4 chữ số;

Digit: Chữ số

Position: Vị trí