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Sample Size Required to Achieve a Desired Confidence Level

(with proportion defective = 0.05)

p=0.05

Number of Failures

Confidence Levels

60%

80%

90%

95%

99%

0 18 32 46 59 90
1 40 60 77 94 130
2 62 85 106 125 166
3 84 110 133 154 198
4 105 134 159 180 228
5 126 157 184 208 258
6 147 180 209 235 288
7 168 204 234 260 317
8 189 227 258 286 344
9 209 249 282 310 370
10 230 272 306 336 397
11 251 294 330 361 423
12 271 317 354 386 448
13 292 339 378 413 479
14 307 360 400 435 506
15 333 383 424 462 531
16 354 405 448 485 557
17 375 427 472 507 580
18 395 449 493 531 606
19 416 471 516 555 633
20 436 493 538 578 657
22 477 537 583 624 706
24 518 580 628 672 756
26 559 623 674 717 808
28 603 668 718 763 850
30 640 710 763 811 900
35 743 818 877 927 1034
40 845 923 986 1036 1157
45 947 1029 1096 1148 1274
50 1052 1135 1200 1260

1350



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