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PROBLEM. 
Given the number of times in which an unknown 
event has happened and failed : Required the chance 
that the probability of its happening in a fingle trial 
lies fomewhere between any two degrees of pro- 
bability that can be named. 
SECTION I. 
F) EFINITION i. Several events are in- 
confident) when if one of them happens, none 
of the reft can. 
2. Two events are contrary when one, or other of 
them muft ; and both together cannot happen. 
3. An event is faid to jail , when it cannot hap- 
pen i or, which comes to the fame thing, when its con- 
trary has happened. 
4. An event is faid to be determined when it has 
either happened or failed. 
5. The probability oj any event is the ratio between 
the value at which an expe&ation depending on the 
happening of the event ought to be computed, and 
the value of the thing expected upon it’s happening. 
6. By chance I mean the fame as probability. 
7. Events are independent when the happening of 
any one of them does neither increafe nor abate the 
probability of the reft. 
When; federal events are inconfiftent the probabili- 
ty of the happening of one or other of them is the 
fum of the probabilities of each of them. 
Suppofe 
