Subject: mathqa
Question: at a summer camp with 2100 participants , 1 / 2 of the campers are aged 8 to 12 . next year , the number of campers aged 8 to 12 will increase by 1 / 3 . after this change , what percentage of the total 2100 campers will the 8 - to 12 - year - olds represent ?
Option: 
A: 62
B: 66
C: 66 2 / 3
D: 68
Answer: C