Q. Kevin is \(3\) times as old as Daniel. \(4\) years ago, Kevin was \(5\) times as old as Daniel.How old is Kevin now?
Define Ages: Let's denote Kevin's current age as K and Daniel's current age as D. According to the problem, Kevin is 3 times as old as Daniel, which gives us the equation:K=3D
Equation 1: The problem also states that 4 years ago, Kevin was 5 times as old as Daniel. We can represent their ages 4 years ago as K−4 for Kevin and D−4 for Daniel. The equation based on this information is:K−4=5(D−4)
Equation 2: Now we will expand the equation from the previous step to solve for D:K−4=5D−20
Expand Equation: Since we know from the first step that K=3D, we can substitute 3D for K in the equation:3D−4=5D−20
Substitute K: Next, we will solve for D. To do this, we will move all terms involving D to one side and the constant terms to the other side:3D−5D=−20+4
Solve for D: Simplifying the equation gives us:−2D=−16
Finalize D: Dividing both sides of the equation by −2 to solve for D gives us:D=−16/−2D=8So, Daniel is currently 8 years old.
Find Kevin's Age: Now that we know Daniel's age, we can find Kevin's age by using the first equation K=3D: K=3×8K=24Therefore, Kevin is currently 24 years old.
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