Skip to content / Đến nội dung
ThichHocToan.com

Australian AMC 2019 - Intermediate Question 26

AMC AUSTRALIA · Australian AMC 2019 - Intermediate

Question 26

A positive whole number is called stable if at least one of its digits has the same value as its position in the number. For example, 78247 is stable because a 4 appears in the 4th position. How many stable 3-digit numbers are there?