1 1/6 hrs.....1 hr = 60 minutes......1/6 hr = 1/6(60) = 60/6 = 10 minutes....therefore, 1 1/6 hrs = 70 minutes
(7/8) / 70 = x / 1....7/8 of the wall to 70 minutes = x wall in 1 minute
cross multiply
(70)(x) = (7/8)(1)
70x = 7/8
x = (7/8) / 70
x = 7/8 * 1/70
x = 7 / 560 reduces to 1/80 <== she paints 1/80 of the wall in 1 minute