Answer:
b = 2c: Ben's age is twice Cindy's. So Cindy is 15 years old
(a + b + c) / 3 = 28: Their average age is 28 This tells us nothing as we already have Anne, Ben and Cindy's ages. It does however give us a quick way to check the answers:
[tex]\frac{a + b + c}{3} = 28\\\frac{39 + 30 + 15}{3} = 28\\\frac{84}{3} = 28[/tex]
Correct, so we know values found are correct.
