Question 1196713: A boy Is 10 years old and his mother is 37 years old. In how many years time will the mother be twice as old as her son Found 2 solutions by ikleyn, greenestamps:Answer by ikleyn(52775) (Show Source):
Let the unknown number of years will be x.
Then you have this equation
37 + x = 2*(10+x)
Simplify and find x
37 + x = 20 + 2x
37 - 20 = 2x - x
17 = x.
ANSWER. In 17 years.
While a formal algebraic solution was probably wanted, you can get good problem-solving experience and good mental exercise by solving the problem using logical reasoning and simple arithmetic.
The difference in their ages is 37-10 = 27, so when the mother will be twice as old as her son their ages will be 54 and 27. Since the mother is now 37, that will be in 54-37 = 17 years.
