Answer
The probability of winning a lottery with one lottery ticket is the number of ways of winning, which is precisely $1$, divided by the total number of possible combinations.
Work Step by Step
In equation form:
$ P\left( E \right)=\frac{\ \text{number}\ \text{of}\ \text{ways}\ \text{of}\ \text{winning}}{\text{total}\ \text{number}\ \text{of}\ \text{combinations}}$