Describe the error in the work shown below.
find an expression equivalent to 18 + 30.
factors of 18: 1, 2, 3, 6, 9, 18
factors of 30: 1, 2, 3, 5, 6, 10, 15, 30
18 + 30 = 6(3 + 10)

For the chance to be team captain, the numbers 1-30 are put in a hat and you get two chances to pick a number, without replacement. which formula correctly shows how to find the probability that you choose the number 1 and then 2?