See a similar Question that I answered here:
https://web2.0calc.com/questions/americam-women-shoe-size
8.35 - 1 S.D. = 6.88 which means 34.1 + 50 % = ~84.1% have a shoe size 'at least' 6.88 ~15.9% have a shoe size less than 6.88
(The problem wording is 'at least' 84.1% have a shoe size BIGGER than 6.88 <======is that what 'at least' means here? )