Q. Kevin is \(3\) years older than Daniel. Two years ago, Kevin was \(4\) times as old as Daniel.How old is Kevin now?
Equation 1: Kevin's age: Let's denote Kevin's current age as K and Daniel's current age as D. According to the problem, Kevin is 3 years older than Daniel, which gives us our first equation:K=D+3
Equation 2: Kevin's age two years ago: The problem also states that two years ago, Kevin was 4 times as old as Daniel. Two years ago, Kevin's age would have been K−2 and Daniel's age would have been D−2. The second equation based on this information is:K−2=4×(D−2)
System of equations: Now we have a system of two equations:1) K=D+32) K−2=4×(D−2)We can use substitution or elimination to solve this system. Let's use substitution since we already have K expressed in terms of D from the first equation.
Substitution method: Substitute K from the first equation into the second equation:(D+3)−2=4×(D−2)Now, let's solve for D.
Solving for D: Simplify the equation:D+1=4D−8Now, let's move all terms involving D to one side and the constant terms to the other side.
Simplifying the equation: Subtract D from both sides and add 8 to both sides:D+1−D=4D−D−8+81=3DNow, divide both sides by 3 to solve for D.
Moving terms and constants: Dividing both sides by 3 gives us:D=31This is a math error because we expect D to be a whole number since it represents an age. Let's go back and check our calculations.
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