OK then let's make an assumption that the rate of expansion has been constant at 67 kilometers per megaparsec per second for the last billion years.

By definition of the Hubble constant

(1) H = v[sub:95kyh845]object[/sub:95kyh845]/d[sub:95kyh845]object[/sub:95kyh845]

or v[sub:95kyh845]object[/sub:95kyh845] = H d[sub:95kyh845]object[/sub:95kyh845]

(2) How far was the object,

d[sub:95kyh845]object[/sub:95kyh845] = ct

Substitute (2) into (1),

(3) v[sub:95kyh845]object[/sub:95kyh845] = Hct

How far did the object move since then?

(4)d[sub:95kyh845]new[/sub:95kyh845] = v[sub:95kyh845]object[/sub:95kyh845]t = (Hct) t = Hct[sup:95kyh845]2[/sup:95kyh845] = 20 Million light-years.

EDIT: equation #