"My mother was 27 years old when I was born. 8 years ago, she was twice as old as
I will be in 5 years time. How old am I."
What sort of maths question is this?
I came up with an answer of 13 years old by adding the 8 and 5 together.
Hello! This is a story problem (also called word problem), and they generally test concepts' comprehension and reasoning skills.
This type of exercise can be given to beginning algebra students, to see whether they can write an equation that models the given information and then solve the equation to find the answer.
But, algebra is not required. This exercise could also be given in an arithmetic class, as practice for abstract thinking, reasoning skills and logical deduction, because, after understanding the given scenario, the exercise can be solved by making a guess, checking, followed by refining the guess to check again.
Let's test your guess that the daughter is 13 years old now.
If so, then her mother is 40 years old now (because thirteen years ago, her mother was 27 years old).
27 + 13 = 40
Okay. Eight years ago, the mother's age was twice what the daughter's age will be five years from now.
Well, eight years ago, the mother's age was 32 (40 - 8 = 32).
Five years from now, the daughter's age will be 18 (13 + 5 = 18).
But, 32 is not twice 18, so you need to guess again. Hint: guess smaller and smaller ages, rechecking, and eventually you'll find the solution.
If your granddaughter is actually taking a beginning algebra class, and she needs help writing and/or solving an equation, please have her post her work or thoughts thus far, and we can help her finish it.
To start an algebraic approach:
Let x = the daughter's age today
Then x + 27 = the mother's age today
Eight years ago, the mother's age was x + 27 - 8
Five years from now, the daughters age will be x + 5
And continue ...
:cool:
