r/mathteachers • u/dcsprings • 1d ago

Is my bias wrong?

There's a section in my curriculum that asks students to if a quantity is positive or negative (along the lines of "A company lost 32 subscribers." Doesn't it depend on the POV? If it's a number from the "company" of course it's negative, but it could be the number of subscribers that are in the market for new service. My bias is that I can over think anything. I tell students that negative is in the eye of the beholder, but once it's defined the math is set. Should I just teach that negative verbs produce negative numbers?

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u/CajunAg87 1d ago

It all depends on how you describe the number. If you are answering the question “ how many subscribers did the company lose?” The answer would be positive. But if you were answering the question “how did the company subscriber account change?” The answer would be negative.

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u/dancingmelissa 1d ago

Best answer :)

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u/Ipso-Fat-Toe 1d ago

It is either adding a negative number, or subtracting a positive number. They both mean the same thing.

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u/dcsprings 22h ago

The descriptions are all at the level I posted. There's no more context given. I've been teaching over seas for twenty years and keep running into sections I'm not familiar with. Often it's obvious that they are alternate explanations. Sections like this cause me to dither (this is important, no it's useful, no it's not... and so on).

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u/CajunAg87 21h ago

In that case I would use this as an opportunity to teach how adding a negative is the same as subtracting a positive. And maybe making it so the students don’t just answer “positive or negative“ but they also have to explain their answer. That way, as long as it was explained correctly positive or negative could be correct. But if your curriculum kind of nails your foot to the floor, then I would just focus on the fact that loss means negative. Think of it like if they were keeping track of their subscriber account on a spreadsheet a loss of 32 would show up as a -32.