Probability

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In order of increasing difficulty (approximately).

Everything

30 31 26 1202 22 1184 32 47 29 1205 1445 2193 1283 1966 2262 50 25 1444 1130 1086 1045 34 2372 847 27 10 1016 1882 1048 33 1111 37 1865 38 174 24 51 53 472 1537 805 852 962 1021 1071 1150 1190 1269 1265 1450 534 1906 1930 1955 158 262 607 309 352 339 636 639 652 654 772 832 987 1051 2138 1167 1213 1428 1508 1536 502 1650 1735 1885 1247 757 787 790 817 905 940 1285 1448 1485 1506 1555 1651 1689 1747 1928 2199 314 48 1491 389 945 371 1540 1155 480 538 2013 627 1696 674 1040 734 1041 1557 2408 2395 875 1232 2172 1857 329 1231 1025 1912 1769 1771 1177 1043 1913 2364 1100 1994 1990 86 192 494 206 236 249 774 2116 567 280 375 464 2256 453 766 781 435 676 208 104 380 39 391 332 272 239 49 44 767 661 695 420 692 2397

50-50 probability trick

1537

Area

1491

Assign variables write equations

39

Basic

31 33

Bayes

51 772 832 48 2408 774 39 49

Be careful

1491

Bernoulli

47 48

Block walking

44

Cases with probability

50 24 639

Casework

639 86 192

Complementary counting

86

Constructive counting

27

Constructive probability

26 47 29 25 847 10 24 53 502 48 49

Divisibility tests

2372

Floor & ceiling

695

Geometric probability

652 1491 945 464 435 49 695

No two adjacent

852 104

Overcounting

30

Polar form

1491

Principle of inclusion-exclusion

389

Probability of AND

38 49

Processes

627 2364 44

Recursion

192 453 239

State diagrams

1857 2364 44

Symmetric outcomes are equally likely

22 32 34 37

Symmetry in counting

380

Triangle inequality

435

Try them all

2372

Not Classified Yet

1202 1184 1205 1445 2193 1283 1966 2262 1444 1130 1086 1045 1016 1882 1048 1111 1865 174 472 805 962 1021 1071 1150 1190 1269 1265 1450 534 1906 1930 1955 158 262 607 309 352 339 636 654 987 1051 2138 1167 1213 1428 1508 1536 1650 1735 1885 1247 757 787 790 817 905 940 1285 1448 1485 1506 1555 1651 1689 1747 1928 2199 314 371 1540 1155 480 538 2013 1696 674 1040 734 1041 1557 2395 875 1232 2172 329 1231 1025 1912 1769 1771 1177 1043 1913 1100 1994 1990 494 206 236 249 2116 567 280 375 2256 766 781 676 208 391 332 272 767 661 420 692 2397

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