Question 184018
To get the rate of hedge clipping with them working
together, I add the rates of them each working alone
In words:
(1 trimming job)/(Lourde's time) + (1 trimming job)/(Rafael's time) =
(1 trimming job)/(time working together)
given:
Lourde's time is {{{8}}} hrs
Rafael's time is {{{15}}} hrs
----------------------------
{{{1/8 + 1/15 = 1/t}}}
Multiply both sides by {{{120}}}
{{{15 + 8 = 120/t}}}
Multiply both sides by {{{t}}}
{{{15t + 8t = 120}}}
{{{23t = 120}}}
{{{t = 5.22}}} hrs
{{{.22*60 = 13.2}}}
Working together, they finish in about 5 hrs and 13 min