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Rule of Sum and Rule of Product
Seek simple and succinct solutions in these systems by sussing-out the significant symmetries.
Excel in math and science
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A palindrome is a number that reads the same forwards and backwards (like 747). Which of the following numbers is a palindrome?
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by Brilliant Staff
How many 3-digit palindromes are there? (Note: The first digit of a 3-digit number must be nonzero.)
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If \(A\) is the number of 3-digit palindromes and \(B\) is the number of 4-digit palindromes, which is greater?
Excel in math and science
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How many 3-digit palindromes are there where the middle digit is larger than the outer digits (like 121)?
Excel in math and science
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How many 3-digit palindromes are there where the middle digit is the same as the leading digit?
Excel in math and science
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by Brilliant Staff