Q. Kevin is \(3\) times as old as Daniel. \(4\) years ago, Kevin was \(5\) times as old as Daniel.How old is Daniel now?
Denoting Kevin and Daniel: Let's denote Kevin's age as K and Daniel's age as D. According to the problem, Kevin is 3 times as old as Daniel. We can write this as an equation:K=3D
Equation 1: Kevin is 3 times Daniel: The problem also states that 4 years ago, Kevin was 5 times as old as Daniel. We can represent this with another equation:K−4=5(D−4)
Equation 2: 4 years ago, Kevin was 5 times Daniel: Now we have a system of two equations:1) K=3D2) K−4=5(D−4)We can use the first equation to substitute K in the second equation.
Substituting K in Equation 2: Substituting K from the first equation into the second equation gives us:3D−4=5(D−4)Now we will solve for D.
Solving for D: Expanding the equation, we get:3D−4=5D−20Now, we will move all terms involving D to one side and constants to the other side.
Moving terms and constants: Subtracting 3D from both sides, we get:−4=2D−20Adding 20 to both sides gives us:16=2D
Solving for D: Dividing both sides by 2 to solve for D, we get:D=8So, Daniel is 8 years old now.
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