3 Digits Plus 3 DigitsDate: 12/09/2001 at 14:41:51 From: Jake Cordell Subject: Maths Use the digits 1 to 9 only once in a sum that must be a three-digit number plus another three-digit number to equal another three-digit number. Each digit can only be used once, but all must be used. Date: 12/09/2001 at 17:30:10 From: Doctor Sarah Subject: Re: Maths Hi Jake - thanks for writing to Dr. Math. The key here is that you will need a sum greater than 10 in the second row so as to be able to carry one to the first row when you add. I'll give you one possibility for the second and third rows - see if you can come up with the first row: x 9 4 x 8 2 ----------- x 7 6 Once you've found one solution, figure out how many ways you can switch the numbers to get another one. (Hint: you can exchange 4 and 2 and they will still add up to 6.) Can you figure it out? - Doctor Sarah, The Math Forum http://mathforum.org/dr.math/ |
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