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Kevin: "When I add 3 times my age 3 years from now to 4 times my age 4 years from now, I get 8 times my current age. How old will I be 2 years from now?" Answer:Answer:27

Solution:

"Let x be my present age. My age 3 years from now will be x + 3, and 3 times that will be 3 (x + 3). Similarly, my age 4 years from now will be x + 4, and 4 times that will be 4 (x + 4).

Adding the two gives 8 times my current age. This gives the equation:

3 (x + 3) + 4 (x + 4) = 8 x.

Solving the above equation gives

x = (3 × 3) + (4 × 4) = 25.

Thus, I will be 27 years old 2 years from now."

Food for thought:

How do you verify the answer?
It's easy! By substitution, right?