### Home > A2C > Chapter 1 > Lesson 1.2.4 > Problem1-119

1-119.

Have you ever wondered why so many equations are written with the variables $x$ and $y$? Suppose you are reaching into a bag that contains all the letters of the English alphabet, and you pull out one letter at random to use as a variable in equations. What is the probability that you pull out an $x$? If you got the $x$, now what is the probability that you pull out a $y$?

$P=\frac{x'\text{s}}{\text{alphabet}}$

After you take out $x$, how many letters are left in the alphabet?