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MATH / The sum of four two-digit numbers is 221. None of the eight digits is 0 and no two of them are the same. Which of the digits 1 through 9 does not appear in one of the four two-digi…

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problem

The sum of four two-digit numbers is 221. None of the eight digits is 00 and no two of them are the same. Which of the digits 11 through 99 does not appear in one of the four two-digit numbers?
Plain-text mathematical notation (without MathML)
The sum of four two-digit numbers is 221. None of the eight digits is 0 and no two of them are the same. Which of the digits 1 through 9 does not appear in one of the four two-digit numbers?
Original LaTeX notation
The sum of four two-digit numbers is 221. None of the eight digits is $0$ and no two of them are the same. Which of the digits $1$ through $9$ does not appear in one of the four two-digit numbers?

level

Level 5

type

Number Theory

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