Unit 2 · Number Theory
Smallest + Largest with 3 Different Digits?
Lesson 14 of 15
About this lesson
Smallest 3-digit number with 3 different digits: hundreds=1 (can't use 0), tens=0, units=2 → 102. Largest: hundreds=9, tens=8, units=7 → 987. Sum = 102 + 987 = 1089. The classic mistake is thinking 100 or 101 qualify — they only have two distinct digits.
Chapters
Question
Sean writes down the smallest 3-digit number that has three different digits.
Tammy writes down the largest 3-digit number that has three different digits.
What is the sum of their two numbers?
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