Prime numbers

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Prime numbers

by gmatrant » Tue Nov 13, 2007 3:25 am
How to solve this?
I took an educated guess. Since I thought that it was possible to solve for both independently.
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by ri2007 » Tue Nov 13, 2007 4:43 am
logically I would also go with D

Stat 1) Tells us there are 100 prime numbers bet 1 and p+1. So if we looked up the first 100 prime numbers, the 100th one would be p

stat 2) Again we can look up the no of prime nos. in the given range and and that no.

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A Concern

by jcan-gmatter » Tue Nov 13, 2007 11:20 am
I would think that the answer is B. For A, is it saying that p is the 100th prime number + 1 OR is it that p is the # after the 100th prime number + 1?

Assuming that 123 is the 100th prime #, then p could be either 123 + 1 or 124 + 1.

Does the above make sense?

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by enlightenment » Tue Nov 13, 2007 11:49 am
I say D as well

1) The first 100 prime numbers from 1 to p+1... counting the first 100 primes we end on 541. Then plus 1 we get 542. So from 1 to 542 there are 100 prime numbers. Sufficient

2) There are 541 prime numbers from 1 to 3912. I found a list of prime numbers on line.

Count for yourself. 4x125 +1 = 541
2 3 5 7
11 13 17 19
23 29 31 37
41 43 47 53
59 61 67 71
73 79 83 89
97 101 103 107
109 113 127 131
137 139 149 151
157 163 167 173
179 181 191 193
197 199 211 223
227 229 233 239
241 251 257 263
269 271 277 281
283 293 307 311
313 317 331 337
347 349 353 359
367 373 379 383
389 397 401 409
419 421 431 433
439 443 449 457
461 463 467 479
487 491 499 503
509 521 523 541
547 557 563 569
571 577 587 593
599 601 607 613
617 619 631 641
643 647 653 659
661 673 677 683
691 701 709 719
727 733 739 743
751 757 761 769
773 787 797 809
811 821 823 827
829 839 853 857
859 863 877 881
883 887 907 911
919 929 937 941
947 953 967 971
977 983 991 997
1009 1013 1019 1021
1031 1033 1039 1049
1051 1061 1063 1069
1087 1091 1093 1097
1103 1109 1117 1123
1129 1151 1153 1163
1171 1181 1187 1193
1201 1213 1217 1223
1229 1231 1237 1249
1259 1277 1279 1283
1289 1291 1297 1301
1303 1307 1319 1321
1327 1361 1367 1373
1381 1399 1409 1423
1427 1429 1433 1439
1447 1451 1453 1459
1471 1481 1483 1487
1489 1493 1499 1511
1523 1531 1543 1549
1553 1559 1567 1571
1579 1583 1597 1601
1607 1609 1613 1619
1621 1627 1637 1657
1663 1667 1669 1693
1697 1699 1709 1721
1723 1733 1741 1747
1753 1759 1777 1783
1787 1789 1801 1811
1823 1831 1847 1861
1867 1871 1873 1877
1879 1889 1901 1907
1913 1931 1933 1949
1951 1973 1979 1987
1993 1997 1999 2003
2011 2017 2027 2029
2039 2053 2063 2069
2081 2083 2087 2089
2099 2111 2113 2129
2131 2137 2141 2143
2153 2161 2179 2203
2207 2213 2221 2237
2239 2243 2251 2267
2269 2273 2281 2287
2293 2297 2309 2311
2333 2339 2341 2347
2351 2357 2371 2377
2381 2383 2389 2393
2399 2411 2417 2423
2437 2441 2447 2459
2467 2473 2477 2503
2521 2531 2539 2543
2549 2551 2557 2579
2591 2593 2609 2617
2621 2633 2647 2657
2659 2663 2671 2677
2683 2687 2689 2693
2699 2707 2711 2713
2719 2729 2731 2741
2749 2753 2767 2777
2789 2791 2797 2801
2803 2819 2833 2837
2843 2851 2857 2861
2879 2887 2897 2903
2909 2917 2927 2939
2953 2957 2963 2969
2971 2999 3001 3011
3019 3023 3037 3041
3049 3061 3067 3079
3083 3089 3109 3119
3121 3137 3163 3167
3169 3181 3187 3191
3203 3209 3217 3221
3229 3251 3253 3257
3259 3271 3299 3301
3307 3313 3319 3323
3329 3331 3343 3347
3359 3361 3371 3373
3389 3391 3407 3413
3433 3449 3457 3461
3463 3467 3469 3491
3499 3511 3517 3527
3529 3533 3539 3541
3547 3557 3559 3571
3581 3583 3593 3607
3613 3617 3623 3631
3637 3643 3659 3671
3673 3677 3691 3697
3701 3709 3719 3727
3733 3739 3761 3767
3769 3779 3793 3797
3803 3821 3823 3833
3847 3851 3853 3863
3877 3881 3889 3907
3911