Question: 4 / 5

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bob and mark talk about their families. bob says he has 3 kids, the product of their ages is 72. he gives another clue: the sum of the ages of his children. mark points out that there is still not enough information to accurately guess. finally, bob says, "my youngest child called justice." mark can then correctly determine the anges of bob's children. what are the ages?

We know that the product of the kid`s ages is 72. It could be: 72 = 2*6*6, 72 = 2*3*12, 72 = 3*4*6; ... But only for two products: 72 = 2*6*6 and 72 = 3*3*8 we have the same sum of the ages ( 2 + 6 + 6 = 14 and 3 + 3 + 8 = 14 ) and that explains why Mark hadn`t enough information when he heard the sum of the ages. After that Bob said: "My youngest child..." so Mark was sure that his friend had just one youngest child ( 3 , 3 , 8 is a wrong combination of ages ). Therefore, the answer is: the youngest child is 2 and other two are both 6 years old.

Ithink if im not mistaking b is -3 but im not a 100% sude