Answer
a. Only one customer receives 20 dollars bills = {XY, YX}
b Both customers receive 10 dollars bills = {XX}
c. At most one customer receives 20 dollars bills = {XX, XY, YX}
d. First customer receives 10 dollars bills and the second receives $20 bills = {XY}
Work Step by Step
Let us denote the customer who receives four 10 dollars bills by X, and the customer who receives two 20 dollars bills by Y.
This experiment has four outcomes, which are shown in the diagram.
XX = Both customers receive four 10 dollars bills.
XY = The first customer receives four 10 dollars bills and the second customer receives two 20 dollars bills.
YX = The first customer receives two 20 dollars bills but the second customer receives four 10 dollars bills
YY = Both adults receive two 20 dollars bills
a. Only one customer receives 20 dollars bills = {XY, YX}
Since this event includes two outcomes, it is a compound event.
b Both customers receive 10 dollars bills = {XX}
Since this event includes only one outcome, it is a simple event.
c. At most one customer receives 20 dollars bills = {XX, XY, YX}
Since this event includes three outcomes, it is a compound event.
d. First customer receives 10 dollars bills and the second receives $20 bills = {XY}
Since this event includes only one outcome, it is a simple event.
