One window washer can wash 30 windows in 2 hours. At this rate, how many windows can be washed in 8 hours by 3 window washers?

Answer 1

1 washer ---- 30 windows ----- 2 hours
3 washers ---- 90 windows ---- 2 hours **
3 washers ----360 windows ---- 8 hours ***

** , used only this part
1 washer ---- 30 windows
3 washers ---- 90 windows

***, used only this part
90 windows ---- 2 hours
360 windows ---- 8 hours

Answer 2

isnt it 720 windows

Answer 3

no
in the last part, the time quadrupled, so the number of window would also quadruple.
2 hrs times 4 = 8 hrs
90 windows times 4 = 360 windows

how did you get 720 ?