'Bi' means 'two' (like a bicycle has two wheels) .. .. so this is about things with two results. |
HHH |
HHT |
HTH |
HTT |
THH |
THT |
TTH |
TTT |
Number of outcomes we want | Probability of each outcome | ||
3 | × | 1/8 | = 3/8 |
Number of outcomes we want | Probability of each outcome | |||
126 | × | 1512 | = | 126512 |
Number of outcomes we want | Probability of each outcome | |||
3 | × | 0.147 | = | 0.441 |
Number of outcomes we want | Probability of each outcome | |||
120 | × | 0.0022235661 | = | 0.266827932 |
X | P(X) | X × P(X) | X2 × P(X) |
0 | 0.0001 | 0 | 0 |
1 | 0.0036 | 0.0036 | 0.0036 |
2 | 0.0486 | 0.0972 | 0.1944 |
3 | 0.2916 | 0.8748 | 2.6244 |
4 | 0.6561 | 2.6244 | 10.4976 |
SUM: | 3.6 | 13.32 |