You can work this out two ways:
1) you can find the percentage of students who have brown hair, and subtract from 100% to find the total percentage of other hair colors,
11 / 25 = 0.44 or 44% > 100% - 44% = 56% < this is the number of students without brown hair,
or
2) you can find out the number of students who have a different hair color, and finding the percentage of that new number:
25 - 11 = 14 < this is the number of students in the class that have a hair color other than brown. To find the percentage:
14 / 25 = 0.56 or 56%
Answer: 56% of students do NOT have brown hair.
