how many minutes are there in 1 1/6 hours?
we count like this:
[tex] 1\frac{1}{6} *60= \frac{7}{6} *60=70[/tex]
so she can paint 7/8 wall in 70 minutes.
how much is it per minute?
[tex] \frac{7}{8*70} = \frac{1}{8*10} = \frac{1}{80}[/tex]
and that's the correct answer!