Given the probability that the event occurs PE find the odds

Given the probability that the event occurs, P(E), find the odds O(E)

Answer using the following notation (3:1, represents 3 to 1 in favor of E).

P(E)=0.20

P(E)=0.03

P(E)=0.15

P(E)=0.45

P(E)=0.78

Given the odds that the event occurs O(E), what is the number of events in the sample space n(S).

O(E)=7:3

O(E)=6:11

O(E)=24:1

O(E)=11:44

O(E)=3:1

I.
O(E) = 0.20 : 0.80 = 1:4
O(E) = 0.03 : 0.97 = 3:97
O(E) = 0.15 : 0.85 = 3:17
O(E) = 0.45 : 0.55 = 9:11
O(E) = 0.78 : 0.22 = 39:11

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