Donald spent half as much as Patricia did on presents this year, and Carl spent 3 times more than Donald. If the total spent between the three of them was $72, how much did they each spend on presents this year?

Patricia spent $24 on presents, while Donald spent $12 and Carl spent $36.

Step-by-step explanation:

The problem is to solve how much money each person spent on presents in the year, through a series of equivalences. In order to determine how much money each one spent, the following equation must be proposed:

Patricia = X

Donald = 1 / 2X

Carl = 3/2 X

X + 1 / 2X + 3 / 2X = 72

1X + 0.5 X + 1.5 X = 72

3X = 72

X = 72/3

X = 24

Thus, Patricia spent $ 24 on presents, while Donald spent $ 12 (2/24) and Carl spent $ 36 (1.5 x 24).