If a number is a multiple of , then the number is divisible by .
The number is .
The number is not a multiple of .
No valid conclusion: The last digit is a .
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, then the number is divisible by ![\"\"](\"http://www.mathskey.com/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=0d25261cbf81e1c8bf5afdeff1f7b3e9.png\")
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.