The total amount of material that is needed for the s scarves is calculated by multiplying s and 1/6. This calculated value should not exceed 8/9 in order for the material to still be enough for the project. The inequality is,
s/6 ≤ 8/9
The value of s from the inequality is 5.33. Therefore, the maximum number of scarves that can be made out of the material available is 5.