We must accept finite disappointment, but we must never lose infinite hope; because the truth does not depend on a consensus of opinion.
Mark:
4 NUMBERS
343,

330

, 325,

324
Thanks buddy, that's my assignment wrapped up!
Letter A - All possible 3 digit cubes are:
125, 216, 343, 512, 729
We can eliminate 125 from this because of the letter C having a minimum of 210. And also 729 because it is also a possible answer for the letter D, leaving us with:
216, 343, 512
Letter B - All possible primes to use are:
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31
Lowest possible number is 2x3x5x7 = 210, therefore, for the letter A we can eliminate 125 as an answer.
Letter C - From the letters A and D and B, we now have a maximum and minimum number possible, which are 532 and 196. So we now list all the possible answers for C that are in between those numbers, which is all the numbers between 20 and 32 (by this I mean if you did 1+2+3....+20, all the way up to 32). The answers each gives is:
210, 231, 276, 300, 325, 351, 378, 406, 435, 465, 496, 528
If we then eliminate any that are more than 20 away from any of our answers to A and D it leaves us with:
210, 231, 325, 351, 496, 528
Letter D - All possible 3 digit squares from 196 to 749 are:
196, 225, 256, 289, 324, 361, 400, 441, 484, 529, 576, 625, 676, 729, 784
We can then eliminate any of these numbers that are more than 20 away from the 4 possible numbers we have for the letter A:
This leaves us with the following:
196, 225, 324, 361, 529
Now we can look at all the possible A, C and D combinations:
1. a) 216 c) 210 d) 196
2. a) 216 c) 210 d) 225
3. a) 216 c) 231 d) 225
4. a) 343 c) 325 d) 324
5. a) 343 c) 351 d) 361
6. a) 512 c) 528 d) 529
Straight away we can rule out numbers 5 and 6 because in those, A is the lowest number and D is the highest. Therefore, no matter where you inserted a value for b), either A would still be the lowest or D would still be the highest.
Lets take a look at the 4 possibilities in more detail:
1. B can only go in between C and A, therefore it must equal between 211 and 215. We know the lowest possible value for B is 210, and the next lowest possible is 2x3x5x11 = 330. Therefore it can't be this solution.
2. B can only go after D for this one to work, meaning it must equal between 226 and 230. Again this is not possible as we know from possibility number 1 above.
3. B can only go before A for this to work, so it can be between 211 and 215. We already know this isn't possible.
4. B can actually in two places here. It could go after A, in which case it must equal 344, or it can go after C, in which case it must be in between 326 and 342. Well we have our answer as we know that the next lowest value of B was 330, which fits in perfectly.
So this leaves us with Mark's answer.
TTH, I am sure your encouragement is appreciated by all.
CBALTTUERDIEESD
CLNINOETD