if we use 0-9 figure like figure used in social security number, how many combinations can we  get using 0-9?
486767
988911099. None of the three fields in a US SSN can zero.
631136
Total 20 nines (2 in 99) are there in 0 to 100.\n\n9, 19, 29, 39, 49, 59, 69, 79, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99
906203
Assuming you cannot reuse a digit unless there is more than one copy in the list...\n\nYou could do it this way...\n5 one-digit numbers: 2, 5, 6, 7, 9\n22 two-digit numbers: 22, 25, 26, 27, 29, 52, 56, 57, 59, 62, 65, 66, 67, 69, 72, 75, 76, 79, 92, 95, 96, 97\netc.\n\nBut it would take a while. The answer is: at least a few.
1029989
The answer is 120 "lock combos" if I've understood your question.\n\nYou can't use a number twice, but different orders are allowed, but a combo must end in 0. So, for example, 2450 and 5240 are valid combo numbers. If that's the case, the answer is 120.\n\nYou must choose 3 distinct numbers in any order from the numbers 2 4 5 6 7 8. You then add a 0 on the end of these 3 to get a  valid 4 digit combo number. The number of ways of doing this is simply 6x5x4 = 120. Note, if digits could be used more than once it would 6x6x6 = 216.\nAs far as using formulas go, you would use the permutation formula: \n\nnPr = n!/(n-r)! In your case n= 6 and r = 3\n\n6P3 = 6x5x4 = 120
578863
Yes. The first three digits are the area number. They represent the state or U.S. possession where the number was issued -- NOT the country. The second two digits are the group number. Numbers are assigned starting in the Northeast, so people on the West coast have higher numbers than those on the East coast. For more information see:\nhttp://en.wikipedia.org/wiki/Social_security_number#Structure\nAnd:\nhttp://www.ssa.gov/employer/stateweb.htm
405265
there are 17,576,000 possible arrangements. First, take the three letters, and find out all the possible combinations that there are for them. This answer turns out to be 17,576. Then take the numbers. There are 1,000 possible arrangements, so the number of possible arrangements for the license plate is 17,576,000.
974244
Its just the whole numbers!\n0000\n0001\n0002\n0003\netc.\nup to\n9999\nremembering that if the number has less than 3 digits, you need to add the appropriate number of zeroes at the beginning.\n(i.e,. 23 would be 0023 and 456 would be 0456)\n(why anyone would want to 'prove' this or generate them in excel is beyond me. its a fabulous waste of time, unless you needed to print them out.) But if so,maybe you dont have excel:\n0000 0001 0002 0003 0004 0005 0006 0007 0008 0009 0010 0011 0012 0013 0014 0015 0016 0017 0018 0019 0020 0021 0022 0023 0024 0025 0026 0027 0028 0029 0030 0031 0032 0033 0034 0035 0036 0037 0038 0039 0040 0041 0042 0043 0044 0045 0046 0047 0048 0049 0050 0051 0052 0053 0054 0055 0056 0057 0058 0059 0060 0061 0062 0063 0064 0065 0066 0067 0068 0069 0070 0071 0072 0073 0074 0075 0076 0077 0078 0079 0080 0081 0082 0083 0084 0085 0086 0087 0088 0089 0090 0091 0092 0093 0094 0095 0096 0097 0098 0099 0100 0101 0102 0103 0104 0105 0106 0107 0108 0109 0110 0111 0112 0113 0114 0115 0116 0117 0118 0119 0120 0121 0122 0123 0124 0125 0126 0127 0128 0129 0130 0131 0132 0133 0134 0135 0136 0137 0138 0139 0140 0141 0142 0143 0144 0145 0146 0147 0148 0149 0150 0151 0152 0153 0154 0155 0156 0157 0158 0159 0160 0161 0162 0163 0164 0165 0166 0167 0168 0169 0170 0171 0172 0173 0174 0175 0176 0177 0178 0179 0180 0181 0182 0183 0184 0185 0186 0187 0188 0189 0190 0191 0192 0193 0194 0195 0196 0197 0198 0199 0200 0201 0202 0203 0204 0205 0206 0207 0208 0209 0210 0211 0212 0213 0214 0215 0216 0217 0218 0219 0220 0221 0222 0223 0224 0225 0226 0227 0228 0229 0230 0231 0232 0233 0234 0235 0236 0237 0238 0239 0240 0241 0242 0243 0244 0245 0246 0247 0248 0249 0250 0251 0252 0253 0254 0255 0256 0257 0258 0259 0260 0261 0262 0263 0264 0265 0266 0267 0268 0269 0270 0271 0272 0273 0274 0275 0276 0277 0278 0279 0280 0281 0282 0283 0284 0285 0286 0287 0288 0289 0290 0291 0292 0293 0294 0295 0296 0297 0298 0299 0300 0301 0302 0303 0304 0305 0306 0307 0308 0309 0310 0311 0312 0313 0314 0315 0316 0317 0318 0319 0320 0321 0322 0323 0324 0325 0326 0327 0328 0329 0330 0331 0332 0333 0334 0335 0336 0337 0338 0339 0340 0341 0342 0343 0344 0345 0346 0347 0348 0349 0350 0351 0352 0353 0354 0355 0356 0357 0358 0359 0360 0361 0362 0363 0364 0365 0366 0367 0368 0369 0370 0371 0372 0373 0374 0375 0376 0377 0378 0379 0380 0381 0382 0383 0384 0385 0386 0387 0388 0389 0390 0391 0392 0393 0394 0395 0396 0397 0398 0399 0400 0401 0402 0403 0404 0405 0406 0407 0408 0409 0410 0411 0412 0413 0414 0415 0416 0417 0418 0419 0420 0421 0422 0423 0424 0425 0426 0427 0428 0429 0430 0431 0432 0433 0434 0435 0436 0437 0438 0439 0440 0441 0442 0443 0444 0445 0446 0447 0448 0449 0450 0451 0452 0453 0454 0455 0456 0457 0458 0459 0460 0461 0462 0463 0464 0465 0466 0467 0468 0469 0470 0471 0472 0473 0474 0475 0476 0477 0478 0479 0480 0481 0482 0483 0484 0485 0486 0487 0488 0489 0490 0491 0492 0493 0494 0495 0496 0497 0498 0499 0500 0501 0502 0503 0504 0505 0506 0507 0508 0509 0510 0511 0512 0513 0514 0515 0516 0517 0518 0519 0520 0521 0522 0523 0524 0525 0526 0527 0528 0529 0530 0531 0532 0533 0534 0535 0536 0537 0538 0539 0540 0541 0542 0543 0544 0545 0546 0547 0548 0549 0550 0551 0552 0553 0554 0555 0556 0557 0558 0559 0560 0561 0562 0563 0564 0565 0566 0567 0568 0569 0570 0571 0572 0573 0574 0575 0576 0577 0578 0579 0580 0581 0582 0583 0584 0585 0586 0587 0588 0589 0590 0591 0592 0593 0594 0595 0596 0597 0598 0599 0600 0601 0602 0603 0604 0605 0606 0607 0608 0609 0610 0611 0612 0613 0614 0615 0616 0617 0618 0619 0620 0621 0622 0623 0624 0625 0626 0627 0628 0629 0630 0631 0632 0633 0634 0635 0636 0637 0638 0639 0640 0641 0642 0643 0644 0645 0646 0647 0648 0649 0650 0651 0652 0653 0654 0655 0656 0657 0658 0659 0660 0661 0662 0663 0664 0665 0666 0667 0668 0669 0670 0671 0672 0673 0674 0675 0676 0677 0678 0679 0680 0681 0682 0683 0684 0685 0686 0687 0688 0689 0690 0691 0692 0693 0694 0695 0696 0697 0698 0699 0700 0701 0702 0703 0704 0705 0706 0707 0708 0709 0710 0711 0712
474532
a couple of years ago i discovered my social security number has 6 six's inside of the numbers, it scares the daylights out of me, i wonder who the hell would have 666-666-6666??
924460
It depends on whether you allow a leading zero or not. \nIf you are allowed a leading 0, its easy. The last digit can be 0,2,4, or 6 (4 possibilities), and after you've chosen that, theres 7 possibilities for the first digit and 6 possibilities for the second digit, which makes 4*7*6 = 168.\nHowever, usually 3 digit numbers can't have leading zeroes. Now we have to split it up into two cases:\nCase 1:\n_ _ 0\nThere are 7 choices for the first digit, and 6 choices for the second - 42 possibilities.\nCase 2:\nIt ends with a 2, 4, or 6.\nThere are now 3 choices for the last digit, 6 choices for the first digit (anything *but* 0), and 6 choices for the second digit - 3*6*6 = 108.\nSo the total is 150.\n\nNote that we dealt with the 0 case specially, because it made a difference whether we had a 0 to work with for the first digit or not.\n\n(Note - again, in response to Wal C below, you *have* to split it up into cases. He said 4*6*6; however, if you happened to choose the 0 for the last digit as part of that '4', there will be *7* possibilities for the first digit, not 6. So you can't do it all together like that.)
520096
a) That means the number has to start with 5\nso you only need to choose the second and third digits.\nThere are 4 choices for the second and 3 choices for the third\n4*3 = 12\nb) The first digit must be 1 or 2\n2 choices for the first 1\n4 choices for the second \n3 choices for the third\n2*4*3 = 24\nEDIT: I read the part b incorrectly. This is the answer if no repetitions are allowed.\nIf repetitions are allowed, then you still have 5 choices for the second and third digits.\n2*5*5 = 50
880056
Easy way to remember...\n\n(1) the digits in the multiples of 9 also equal 9 when added together such as 18 (1+8=9) and 45 (4+5=9).\n\n(2) multiples of 9 less than 100 'reverse' half way thru (09 & 90, 18 & 81, 27 & 72, 36 & 63, etc.)\n\n(3) start with 09 and add 1 to the tens column and subtract 1 from the ones column. (09, 18, 27, 36, 45, etc)
919791
A Social Security Number (SSN) consists of nine digits, commonly written as three fields separated by hyphens: AAA-GG-SSSS. The first three-digit field is called the "area number". The central, two-digit field is called the "group number". The final, four-digit field is called the "serial number".\n\nThe process of assigning numbers has been changed at least twice. Until 1965, only half the group numbers were used. Before 1972, numbers were assigned by field offices; since 1972, they have all been assigned by the central office. The order in which numbers were assigned was changed in the 1972 transition. There may have been other changes, but it's difficult to get information on how things used to be done.\n\nArea Numbers\nThe area numbers are assigned to geographical locations. They were originally assigned the same way that zip codes were later assigned (in particular, area numbers increase from east to west across the continental US as do the ZIP codes). Most area numbers were assigned according to state (or territorial) boundaries, although the series 700-729 was assigned to railroad workers regardless of location (this series of area numbers was discontinued in 1964 and is no longer used for new SSNs). Area numbers assigned prior to 1972 are an indication of the SSA office which originally issued the SSN. Since 1972 the area number in SSNs corresponds to the residence address given by the applicant on the application for the SSN.\n\nIn many regions the original range of area number assignments was eventually exhausted as population grew. The original area number assignments have been augmented as required. All of the original assignments were less than 585 (except for the 700-729 railroad worker series mentioned above). Area numbers of "000" have never been issued.\n\n  001-003 NH    400-407 KY    530     NV \n  004-007 ME    408-415 TN    531-539 WA\n  008-009 VT    416-424 AL    540-544 OR\n  010-034 MA    425-428 MS    545-573 CA\n  035-039 RI    429-432 AR    574     AK\n  040-049 CT    433-439 LA    575-576 HI\n  050-134 NY    440-448 OK    577-579 DC\n  135-158 NJ    449-467 TX    580     VI Virgin Islands\n  159-211 PA    468-477 MN    581-584 PR Puerto Rico\n  212-220 MD    478-485 IA    585     NM\n  221-222 DE    486-500 MO    586     PI Pacific Islands*\n  223-231 VA    501-502 ND    587-588 MS\n  232-236 WV    503-504 SD    589-595 FL\n  237-246 NC    505-508 NE    596-599 PR Puerto Rico\n  247-251 SC    509-515 KS    600-601 AZ\n  252-260 GA    516-517 MT    602-626 CA\n  261-267 FL    518-519 ID    627-645 TX\n  268-302 OH    520     WY    646-647 UT\n  303-317 IN    521-524 CO    648-649 NM\n  318-361 IL    525     NM    *Guam, American Samoa, \n  362-386 MI    526-527 AZ     Philippine Islands, \n  387-399 WI    528-529 UT     Northern Mariana Islands\n\n  650-699 unassigned, for future use\n  700-728 Railroad workers through 1963, then discontinued\n  729-799 unassigned, for future use\n  800-999 not valid SSNs.  Some sources have claimed that numbers above 900 were used when some state programs were converted to federal control, but current SSA documents claim no numbers above 799 have ever been used.
1038055
I was told by our computer support person at our office to use a combo of at least 8 digits, including both letters and numbers.  Also, put some of the letters in caps and some in lower case.
427494
The number of combinations is determined by multiplying the number of possible numbers of the first by the number of possible numbers of the second, third and last. If the any of the numbers could be used more than once, the answer would be 4 X 4 X 4 X 4 = 256. Since this problem says that the number can only be used once, then the number of possible choices for the first is 4, the second is only 3, the third is 2, and the last is only 1. So the way to arrive at 24 is 4 X 3 X 2 X 1. Maybe an example to make sure it is clear. If the first digit was 3, then the second could only be one of 5, 8, or 9. If the second was chosen as 5, then the third could only be one of 8 or 9. The last then could only be the one not selected as the third.
668533
There are 3 pairs:\n\n1. 0 and 0\n2. 2 and 2\n3. 9 and 9\n\nThere won't be any more as the number values get larger. This is because when the no.s are multiplied, there would be more digits than when the no.s are added. So they can't be opposite if they have diff. no. of digits.
218967
Only a few answers are possible. One of those is 18, which is used in the example.  All of the possible answers have the same symbol as 18.\n\nSorry, I don't know how to prove this, but try a few examples, always comparing the symbol representing your result to the symbol representing 18.\n\nOkay, I figured it out. \n\nState the puzzle another way:\n\nChoose two one-digit numbers, x and y.\n\nCalculate 10x + y - x - y = 9x\n\nThe result of every calculation is merely 9x.\n\nIn the chart, every multiple of 9 is represented by the same symbol, so no matter what numbers you choose, you get the same symbol.  \n\nWhen you click on the "Click here to try again" link, it merely redraws the table with a different symbol representing the multiples of 9.
1157976
0000, 0001, 0002, 0003, 0004, 0005, 0006, 0007, 0008, 0009, 0010, 0011... etc, etc  untill u get to 9998, 9999\n\ntry it out, might take a long time but one combination will work :))