>>986567If you're mowing a spiral:
area of spiral = area of outside of spiral - area of inside of spiral
area of outmost spiral = 15*10 - 14*9 = 24 m^2
area of next spiral = 14*9 - 13*8 = 22 m^2
area of next spiral = 13*8 - 12*7 = 20 m^2
area of next spiral = 12*7 - 11*6 = 18 m^2
area of next spiral = 11*6 - 10*5 = 16 m^2
area of next spiral = 10*5 - 9*4 = 14 m^2
area of next spiral = 9*4 - 8*3 = 12 m^2
area of next spiral = 8*3 - 7*2 = 10 m^2
area of next spiral = 7*2 - 6*1 = 8 m^2
area of next spiral = 6*1 6 m^2
area of next spiral = 0
You need to mow the three outside spirals (66 m^2) then another 75-66=9m^2 from the next spiral. 9m^2 is 18m of lawnmowing a 0.5m stripe, so one 12m side and almost all of one 7m side.
