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javascriptconverterscurrency

How would calculate the exchange rate of Bitcoin/GBP?

I've got an API that returns the value of: USD/Bitcoin & USD/GBP.

{"USDBITCOIN":"4251.27", "USDGBP":"0.758659"}

To calculate the exchange rate of GBP/Bitcoin, I simply divide the the value of the GBP by Bitcoin, because they are both USD based.

How would calculate the exchange rate of Bitcoin/GBP? It may be really simple, but it's really baffling me. I've got the below to calculate

app.js

xOfy(unit, value) {
  return unit / value;
}

yOfX(unit, value) {
  return unit * value;
}

xOfy(gbp, bitcoin)
// 0.00018

yOfx(bitcoin, gbp)
// 3225.26
Solution

  • You simply divide 1 by the resulting value:

    1 / (USDGBP * USDBITCOIN)

    In this case, that'd be:

    1 / (0.758659 * 4251.27) = 0.0003100521146296338

    The 1 itself comes from the fact 4251.27 USD is how much 1 Bitcoin is worth.