Question 4081
I would do this as follows:
3{{{1/2}}} - {{{1/3}}} - {{{1/3}}}
{{{7/2}}} - {{{1/3}}} - {{{1/3}}}
{{{21/6}}} - {{{2/6}}} - {{{2/6}}}
= {{{17/6}}} = 2{{{5/6}}} pounds left.