From the meaning of the question, we can get two equal relationships: 1, two people buy books with the same money, and Congcong has three times as much money as Mingming. Congcong and Mingming went to the Oriental Bookstore to buy books. Congcong took 74 yuan and Mingming took 50 yuan. Each of them bought a set of fables and spent the same money. Congcong has three times as much money left as Mingming. How much did each of them spend?

Let the book be x yuan, which is derived from the meaning of the question:

74 x = 3(50 x)

You can get x=38.

Two people each used 38 yuan.