There are four marbles in a bag with the colors red, white, blue, and green. john pulls out one marble and tosses a coin. how many elements are there in the sample space?

Elements of sample space = 8

Elements of sample space are the possible outcomes involved in the event. In this case, there are 4 possible outcomes in pulling out one marble since there are 4 available marbles and another 2 outcomes for the tossing of coins. If it is a combined event, then multiplying the different possible outcomes of each event will give the elements of the sample space.

4 * 2 = 8

Looks pretty good to me!