Listen and read the text again. What do these numbers refer to: 40, 4.25? If asked what Jonathan Swift, Oscar Wilde and Samuel Beckett have (0) in common, most people would correctly reply that they are famous writers. But

1 Группа деление и ответ однозначный)56:8=7 ; 56:7=8 ; 54:9=6 ; 54:6=9
2 Группа умножение и ответ двухзначный)  9*6=54;6*9=54;8*7=56;7*8=56