Numerical Puzzle

The five-square numerical puzzle below requires the vertical column to be filled with the digits from a three-digit integral power of 5 and the horizontal row to be filled with the digits from a three-digit integral power of 2. What digit will be in the shaded square?
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Source: NCTM Mathematics Teacher, February 2008

Solution
5^2=25\quad 5^3=125\quad 5^4=625\quad 5^5=3125
2^6=64\quad 2^7=128\quad 2^8=256\quad 2^9=512\quad 2^{10}=1024
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Answer: 6

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About mvtrinh

Retired high school math teacher.
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