Answer:
2 hours and 38 minutes.
Step-by-step explanation:
First we need their hourly rates.
all you have to do now is some adding and dividing:
[tex]50+55=105\\[so together, they wash 110 windows.]\\\\290/110=2.6363636363\\[we can further simplify that to get the hours/minutes format you need:]\\2.63...\\ [turns into] 2\\[hours and] 38 \\[minutes.][/tex]________________________
[tex]2.63636hr=2[hr]+0.63636[hr]\\0.63636hr*60 [mins, 1hr]=38.182min\\38.182min=38min+0.182min\\0.182min*60s1min=10.92s\\10.92s=11s\\[Combining:] 02:38:11\\\\["s", "min" and "hr" are the seconds/minutes and hours.][/tex]