Help

Iam getting 1120..someone plz confirm if it is correct or wrong

As the COM of the two particles will travel along the path of the projectile, So, when the two particles reach the ground, u can get the position of the heavier particle

i.e. TAking the pt. of projection as origin,
m1*(R/2) + m2*x = (m1 + m2)R
So x = 7R/6

u can find R and put..

So, x=1120 m ..

ur ans is correct [1]