Mathematical problems of electronic flea At a certain point K0 on the number axis, the electronic flea picks one unit to K1 to the left, jumps 3 units to K2 from K1 to the right in the second part, jumps 5 units to K3 from K2 to the right in the third part, jumps 7 units to K4 from K3 in the fourth step... Jumps 100 steps according to the above rule, the number shown is 2009 (k100), what is the number shown in the initial position K0 of the electronic flea

Mathematical problems of electronic flea At a certain point K0 on the number axis, the electronic flea picks one unit to K1 to the left, jumps 3 units to K2 from K1 to the right in the second part, jumps 5 units to K3 from K2 to the right in the third part, jumps 7 units to K4 from K3 in the fourth step... Jumps 100 steps according to the above rule, the number shown is 2009 (k100), what is the number shown in the initial position K0 of the electronic flea

Every two jumps of a flea is regarded as an action, which is equivalent to jumping 2 meters to the right. Then 100 steps = 50 actions = jumping 100 meters to the right
So the initial location = 2009-100 = 1909