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C22H19N3O4
09-17-2005, 04:49 AM
Make the number 21 using the numbers:
1, 5, 6, 7

You can use:
addition, subtraction, multiplication, and division.
You can only use each number once and you cant use say 15 (the 1 and the 5 together) and you can't raise the power of any numbers. +1 for the correct answer. :goodjob:

chuck
09-17-2005, 09:22 AM
6/[1-(5/7)] ;)