Question 1059907
Charlie's sister is 3 less than 3 times c if charlie's sister is 9 years old,how old is c 
Equations:
s = 3*c-3
s = 9 yrs
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Solve for "c":
c = (s+3)/3
c = (12)/3 = 4 yrs
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Cheers,
Stan H.
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