First find the number of mice the snake eats each year: 52 weeks/year / 4 weeks/mouse = <<52/4=13>>13 mice/year
Then multiply the number of mice the snake eats per year by the number of years per decade to find the number of mice it eats per decade: 13 mice/year * 10 years/decade = <<13*10=130>>130 mice/decade
#### 130