3digit Numbers
Math brain teasers require computations to solve.
There are four 3digit natural numbers, each of them equals the sum of the cubes of its digits.
Three of them are:
153=1+125+27
370=27+343+0
407=64+0+343
Do you know what the fourth one is? It does not begin with 0, otherwise it isn't a 3digit number.
HintIt's much easier than it seems to be.
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Comments
Jimbo
Dec 12, 2005
 Nice one! I didn't get it but I should have because you gave us the 370 and it should have been obvious from there. Well constructed! 
wolfmanh
Dec 12, 2005
 Sorry, not too good at math ..had to wrk with this for a while and then ask someone WHO I WILL mention........SO ANBARRAESED GREAT TEASER, KEEP THEM COMING. COULD USE A THING OR % LOLOL 
redraptor50
Dec 12, 2005
 I GOT IT .......I GOT IT. Keep them coming!!!! 
lorelle_b
Dec 12, 2005
 Haha...wish I was good at math...lolol anyways great and awesome job. 2 thumbs up 
Brainy_1
Dec 12, 2005
 I'm no good at math, but great teaser! Maybe when I get good at math I will do this one over again! 
precious1026
Dec 12, 2005
 I don't know if this is a Teaser or not. I did not know where to begin. How? 
sweetmama
Dec 12, 2005
 I'm with you precious!! Not to mention that my math skills are not up to par. 
chidam11
Dec 14, 2005
 Nice one Shenqiang. 
mr_brainiac
Jan 01, 2006
 If I'd had a couple of hours to work on it, I would have probably found the answer, but my brain isn't up to the task at the moment. 
trickyone
Jan 02, 2006
 I GOT it was hard though i figured it out because of 370 
javaguru
Jan 02, 2009
 Very nice! I thought it might be tedious, but I figured I could identify a relatively few number of candidates by working out the possible combinations to make the last digit. Each number from 0 to 9 cubed ends in a different digit.
For 0, 0^3 = 0, so the last digits of the other two cubes must add up to 10 so that 10+0 ends with a zero. For 1, 1^3 = 1, so the last digits of the other two cubes must add up to 10 so that 10+1 ends with a 1. As soon as I saw this relationship I realized that any number ending in zero could also end in one and the answer was obvious. Put a smile on my face! 
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