#### Answer

10:9

#### Work Step by Step

The odds in favor of E are found by taking the probability that E will occur
and dividing by the probability that E will not occur.
Odds in Favor = $\frac{P(E)}{P(not E)}$
Using the information given to us in the problem, we find the odds in favor of selecting a tragedy or a history.
E: {10 histories, 10 tragedies}
P(E)= $\frac{20}{38}$ = $\frac{10}{19}$
P(not E) = 1 - P(E)
= 1 - $\frac{10}{19}$
=$\frac{19 - 10}{19}$
= $\frac{9}{19}$
Odds in Favor = $\frac{\frac{10}{19}}{\frac{9}{19}}$ = $\frac{10}{9}$