Step-by-step explanation:
[tex]15 \times 3 = 45 \\ 45 + 1 = 46 \\ 1 \times 10 = 10 \\ 46 + 10 = 56 \\ 56 - 19 = 37 \\ 11 \times 5 = 55 \\ 55 + 37 = 97 \\ 97 - 12 = 80[/tex]
