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Cost of a 128KB computer with floppies in 1985
(sopuli.xyz)
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Whole bunch of low cost 8-bit machines in that era, the Dragon 32, Commodore 64 and Amstrad CPC ranges to name but a few. Of course we must also mention the BBC Micro, was not low cost but every school had one if you grew up in the UK.
We had one in my school in Ireland too (and I think they were common in schools here) but tbh none of the teachers knew how to use it and so we got very little time on it in school.