$1 \leftarrow$ The probability that a bachelor's degree recipient in a certain country in 2018-2019 majored in mathematics is $\frac{39}{100}$. Find the odds of the event occurring. The odds are $\square$ to $\square$. (Simplify your answers.)

Step 1 ：The probability that a bachelor's degree recipient in a certain country in 2018-2019 majored in mathematics is given as \( \frac{39}{100} \).

Step 2 ：The probability of the event not occurring is calculated as \( 1 - \frac{39}{100} = \frac{61}{100} \).

Step 3 ：The odds of an event occurring is defined as the ratio of the probability of the event occurring to the probability of the event not occurring. Therefore, the odds are \( \frac{39}{100} : \frac{61}{100} \).

Step 4 ：This ratio can be simplified by multiplying both sides by 100 to get \( 39 : 61 \).

Step 5 ：Final Answer: The odds are \( \boxed{39} \) to \( \boxed{61} \).