.
Put the original piece of wire onto the number line, from 0 to 6.
Let x be the coordinate, where you cut.
Then the condition that both cuts will be at least 1 in long, is this inequality
1 < x < 5.
So, the cutting position "x" must lie in the segment [1,5] of the entire piece of the length 6.
Hence, the probability under the question is
=
= 66.66%.