Xiao Ming borrowed 500 yuan from his parents, used 970 yuan to buy shoes, returned 10 yuan to his parents, and owed 490 yuan to his parents. The total was 980 yuan, and the total was 990 yuan. Where is the other 10 yuan?

Xiao Ming borrowed 500 yuan from his parents, used 970 yuan to buy shoes, returned 10 yuan to his parents, and owed 490 yuan to his parents. The total was 980 yuan, and the total was 990 yuan. Where is the other 10 yuan?

Xiaoming is the main body of spending money, so we should take Xiaoming as a reference. Xiaoming spent 970 yuan and returned 10 yuan to his parents. There are still 10 yuan in his hand, which adds up to 1000 yuan. The so-called "where's 10 yuan left?"