by darksaber21 » Sun Feb 24, 2013 8:20 am
Here is how I tackled it.
We take one of the numbers and hold it constant. So, lets make p = 0.
So basically, we are left with q + r = 24. Now we can easily figure out the number of combinations for that easily. It is just 25:
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Now, we change p and make it p = 1. If we repeat the process again. We end up with 24 solutions. And when p = 2, there would be 23.
See a pattern? Basically, we end up with the first 25 numbers in sequence, and as such we basically find the 25th triangular number:
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So nsguy1350 was on the right track using triangular numbers, but it was just the nth number you needed, not the sum of the first nth numbers, and it was the wrong nth number too.
Now I know the stakes, and I'm willing to show what I gots. I will see you all at state for the first and final time, so let's end the year with a bang! :)
MTHS - Class 5A, District VII, Region I