If steven is three times older than Keith Bryan is 13 younger than Steve how old are Bryan Keith and steven?

Answer 1

This problem can't be answered because there is insufficient information. There are three unknowns: Brian's age, Steve's age and Keith's age. Call them B, S, and K. You know that S=3K and B+13=S. That is only two equasions to find three unknowns and it can't be done. You must have the same number of equasions (or relationships between the unknowns) as you have unknowns to solve for the unknowns. In this case, three unknowns requires three equasions. Let's make something up and say that we know that the sum of their ages is 36. That would make the third equasion K+B+S=36. What you then do is to substitute the unknowns into the equasions using the reltionships you know so that you have only one unknown in the equasion. Let's solve for Steve's age. First, we know that S=3K. That means K=S/3 (dividing both sides of the equasion by 3). Second, we know that B+13=S. That means B=S-13 (subtracting 13 from both sides of the equasion). Using the third equasion K+B+S = 36, we substitute this information into the third equasion, we have: (S/3)+(S-13)+S=36 or S/3+S-13+S=36 or 2S+S/3=49 or 6S/3 + S/3 = 49 or 7S/3 = 49 or 7S = 147 or S = 21 This means that S=3K or 21/3=K or K=7 and B+13=21 or B=8