Q. Michael is \(3\) times as old as Brandon. \(18\) years ago, Michael was \(9\) times as old as Brandon.How old is Michael now?
Denoting Michael and Brandon: Let's denote Michael's current age as M and Brandon's current age as B. According to the problem, Michael is 3 times as old as Brandon, which gives us our first equation:M=3B
Equation 1: Michael is 3 times as old as Brandon: The problem also states that 18 years ago, Michael was 9 times as old as Brandon. We can express this with a second equation:M−18=9(B−18)
Equation 2: 18 years ago, Michael was 9 times as old as Brandon: Now we have a system of two equations:1) M=3B2) M−18=9(B−18)We can substitute the value of M from the first equation into the second equation to find B.3B−18=9(B−18)
System of equations: Let's solve for B:3B−18=9B−162Now, we'll move all terms involving B to one side and constants to the other side:3B−9B=−162+18−6B=−144
Substituting M into Equation 2: Divide both sides by −6 to find B:B=−6−144B=24So, Brandon is currently 24 years old.
Solving for Brandon's age: Now that we know Brandon's age, we can find Michael's age using the first equation:M=3BM=3×24M=72Michael is currently 72 years old.
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