Pen pals

Two vintage metal postage stamp vending machines. Signs on the machines say: Not in use and Not in service. The machine on the left sells stamps for 2 cents and the machine on the right sells stamps for 5 cents.

Image credit: John West


How long ago do you think that stamps cost this much?

How much do stamps cost today?

How many times more expensive are stamps today than when this machine was in use?

What problems might you encounter if you tried to purchase stamps using this machine today?

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