Grades 5-6 Video Solutions 2015-Level 5&6 Video Solutions 2015 problem25

Level 5&6 Video Solutions 2015 problem25

Video Transcription

Video Summary

In this problem, we're determining the largest possible difference between two pairs of digits, BD and AC, from a four-digit number A, B, C, D, with digits in increasing order. The goal is to maximize the difference between BD and AC. Initial examples with numbers 1234 and 6789 both give a difference of 11. To maximize this difference, the number 1789 is chosen, yielding a larger difference of 61 (79 from BD minus 18 from AC). The conclusion is that 61 is the largest possible difference achievable.

Keywords

digit pairs

maximizing difference

four-digit number

increasing order

largest difference