A rocket is fired from the ground as a projectile. At the top of its trajectory, at a horizontal distance of 260m from the launch point, the rocket breaks into two pieces: One fragment having1/3 of the mass of the original rocket and the remaining piece having 2/3 of the original mass. The smaller piece falls straight down to the ground beneath the break up point while the larger continues on. At what horizontal distance from the launch point does the larger fragment land?

(hint: by one dimensional kinematics, both pieces should hit the ground at the similar time)