2001 AMC 8 Problems/Problem 4
Problem
The digits 1, 2, 3, 4 and 9 are each used once to form the smallest possible even five-digit number. The digit in the tens place is
Solution
Since the number is even, the last digit must be or . To make the smallest possible number, the ten-thousands digit must be as small as possible, so the ten-thousands digit is . Simillarly, the thousands digit has second priority, so it must also be as small as possible once the ten-thousands digit is decided, so the thousands digit is . Similarly, the hundreds digit needs to be the next smallest number, so it is . However, for the tens digit, we can't use , since we already used and the number must be even, so the units digit must be and the tens digit is (The number is .)
See Also
2001 AMC 8 (Problems • Answer Key • Resources) | ||
Preceded by Problem 3 |
Followed by Problem 5 | |
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All AJHSME/AMC 8 Problems and Solutions |
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