Question 151817
Remember:
{{{D[1]}}} = drain 1, 8 days
{{{D[2]}}} = drain 2, 4days
If work together,
={{{(D[1]+D[2])/2}}}
={{{(8+4)/2}}}
={{{12/2}}} = {{{6days}}} ---------------> If 2 work together
Thank you,
Jojo