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Expected Trials Calculator
The purpose of this calculator is to determine the expected number of trials to achieve every possible outcome of repeated random event. To use it, enter into the fields the probability, or number of combinations, for every possible event. If there are less than 19, just use as many fields as you need. Then just click calculate.
For example, consider the question of how many rolls of two dice does it take, on average, to throw every total from 2 to 12? The number of combinations for totals of 2 to 12 goes 1,2,3,4,5,6,5,4,3,2,1. So enter each of those numbers of combinations, click calculate, and you will get the correct answer of 61.217385.