The four blades in a​ four-piece chisel set contain​ cutting-edge widths of one fifth ​in, one half ​in, two thirds ​in, and 1 in. Find the difference in the

Question

The four blades in a four-piece chisel set contain cutting-edge widths of one fifth
in, one half
in, two thirds
in, and 1 in. Find the difference in the cutting-edge width of the two chisels with the widest blades.

Answer 1

1 - 2/3 = 1/3

 

Note that 1/5 = 0.2 < 0.5 = 1/2 

  and 1/2 = 0.5 < 0.6 = 2/3 < 1

Answer 2

1 - 1/5 = ?