Respuesta :

20¢ = 1 postcard

40¢ = 2 postcards

60¢ = 3 postcards

80¢ = 4 postcards

100¢ = 5 postcards

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200¢ = 10 postcards

300¢ 15 postcards

400¢ 20 postcards

500¢ 25 postcards