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AMC10 2027 - Self-practice Set 5 Question 10

AMC10 · AMC10 2027 - Self-practice Set 5

Question 10

The numbers $1,2,\ldots,9$ are randomly placed into the nine squares of a $3\times3$ grid, each used once. What is the probability that every row sum and every column sum is odd?
  1. $\frac1{21}$
  2. $\frac1{14}$
  3. $\frac5{63}$
  4. $\frac2{21}$
  5. $\frac17$