HMMT 十一月 2023 · 冲刺赛 · 第 4 题
HMMT November 2023 — Guts Round — Problem 4
题目详情
- [6] The number 5 . 6 may be expressed uniquely (ignoring order) as a product a.b × c.d for digits a, b, c, d all nonzero. Compute a.b + c.d .
解析
- [6] The number 5 . 6 may be expressed uniquely (ignoring order) as a product a.b × c.d for digits a, b, c, d all nonzero. Compute a.b + c.d . Proposed by: Albert Wang, Karthik Venkata Vedula Answer: 5.1 4 Solution: We want ab × cd = 560 = 2 × 5 × 7. To avoid a zero digit, we need to group the 5 with the 7 to get 3 . 5 and 1 . 6, and our answer is 3 . 5 + 1 . 6 = 5 . 1.