**Answering Problems in Math**

Carey's
Weekly Feature

Many a mark has been lost on math tests when
the wrong answer was written. Deductions, not because students
misunderstood the given information, or came up with procedures
that do not work, or did the math incorrectly, but because in
the final stages of the solution students did not really answer
the question.

For example, would a student writing "x = 240"
acceptably answer the following question?

"A train leaves a station and travels at 40
kilometres per hour. Two hours later a second train leaves the
station and travels at the rate 60 kilometres per hour. Where
will the second train overtake the first?"

A problem with the written answer is x, what
does it represent? Even if x was defined as the distance from
the station where the second train overtakes the first, should
you answer a "where" question with "x equals …". Then is it 240
kilometres, or could it be metres or miles or even minutes?

Clearly 240 metres is nowhere close to the
correct answer and it could not possibly be 240 minutes,
although that is the amount of time it would take the second
train to overtake the first.

240 miles is close to the correct answer, but
a good answer should not be in any way ambiguous. 240 would be a
barely adequate answer only if the problem asked, "how many
kilometres from the station would the second train overtake the
first?"

Even though the student must have done a lot
of good things, "x = 240" does not answer the question "where
will the second train overtake the first?"

Every answer should be given a second look. Is
it reasonable? Is it sufficient? Is there only one way to
interpret what is written? Taking the extra second to look at
your final answer can never be considered a waste of time.

Links discussing problem solving.

The
cure for the "I can't do word problems" syndrome

Mathematical Problem Solving

Learning to Think Mathematically

Links that could help your problem solving
skills.

Request_
Response_ Result

Problem Solving Strategies

Dr. Math: Word Problems

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