A ribbon is 15.9 m long. 3 pieces each 3.6 m long are cut from it and the remainder is cut into 3 equal pieces. How long is each pieces?
The total length of the ribbon is 15.9 m.
Three pieces, each 3.6 m long, are cut from the ribbon, so they have a combined length of 3 x 3.6 = <<3*3.6=10.8>>10.8 m.
The remainder of the ribbon is 15.9 - 10.8 = <<15.9-10.8=5.1>>5.1 m.
The remainder is cut into 3 equal pieces, so each piece will be 5.1 / 3 = <<5.1/3=1.7>>1.7 m long.
Therefore, each of the three equal pieces is 1.7 m long. Answer: \boxed{1.7}.