Art of Problem Solving
AoPS Online
Math texts, online classes, and more
for students in grades 5-12.
Visit AoPS Online ‚
Books for Grades 5-12 Online Courses
Beast Academy
Engaging math books and online learning
for students ages 6-13.
Visit Beast Academy ‚
Books for Ages 6-13 Beast Academy Online
AoPS Academy
Small live classes for advanced math
and language arts learners in grades 2-12.
Visit AoPS Academy ‚
Find a Physical Campus Visit the Virtual Campus

2023 OIM Problems/Problem 1

Revision as of 02:11, 14 December 2023 by Tomasdiaz (talk | contribs) (Created page with "== Problem == Let <math>n</math> be a positive integer. The following 35 multiplications are performed: <cmath>1 \cdot n,2 \cdot n,\cdots ,35 \cdot n</cmath> Show that in at...")
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

Problem

Let $n$ be a positive integer. The following 35 multiplications are performed:

\[1 \cdot n,2 \cdot n,\cdots ,35 \cdot n\]

Show that in at least one of these results the digit 7 appears at least once.

Solution

This problem needs a solution. If you have a solution for it, please help us out by adding it.

See also

https://sites.google.com/associacaodaobm.org/oim-brasil-2023/pruebas

Retrieved from "https://artofproblemsolving.com/wiki/index.php?title=2023_OIM_Problems/Problem_1&oldid=207191"