Are there word problems without an evident unknown?

Question

I teach secondary school maths. I appreciate the expressive precision in which word problems are couched. The unknown is usually stated in question tags at the end. I want to know if this is always the case? Are there no occasions where the authors or mathematician is not precise in expressing himself such that the unknown is explicitly ambiguous? If yes, then is there any algorithm or method by which one can resolve the unknown i.e find out what the unknown is before undertaking to get an equation and then solve the problem?

Answer 1

In general, you want to start by asking yourself "what quantity or quantities do I need to know in this problem?" That gives you your main variable or variables. Then you want to see how to express all the given data in terms of the unknown(s) --- this may require introducing additional variables.