Question 261279
The key to this problem is:
(Dawn's rate of stuffing) + (Brother's rate of stuffing)
= (their rate stuffing together)
The rates are in units of (large party packs)/hour
Dawn's rate = {{{1/6}}}
Let {{{b}}} = Brother's rate of stuffing
given:
{{{1/6 + b = 1/4}}}
{{{b = 1/4 - 1/6}}}
Multiply both sides by {{{12}}}
{{{12b = 3 - 2}}}
{{{b = 1/12}}}
The brother stuffs 1 party pack in 12 hrs working alone