Mia is three years older than twice her sister brooke's age. the sum of their ages is less than 30. what is the greatest age brooke could be?

a.)7

b.)8

c.) 9

d.)10

To find the answer, here is the solution for this problem:
Let M be Mia's age and B for Brooke's age.
M = 2B + 3 
M + B < 30 

M = 30 - B 
30 - B = 2B + 3 
3B = 27 

B = 9
Therefore, Brooke's age is 9 years old. The correct answer would be option C. 
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