Under Gravity

[John O' Meara]

A stone is droped from the top of a cliff of height 256 feet, and, at the same instant, another stone is projected vertically upwards from the ground with a speed of 96 ft/s. Find where they will meet?
I have the following:
v1=u1+at, v2=u2+at, s1=u1t+1/2at^2, s2=u2+1/2at^2,
I also have: v1^2=u1^2+2as1 and V2^2=u2^2+2as2
The question is what do I do next, please?

[Hootenanny]

You have the inital velocity and acceleration of both. You also know that the distance the stone thrown upwards from the ground has travelled when they meet is 256-s where s is the distance travelled by the dropped stone.