Nevermind, but thanks Chi Meson. I was not calculating correctly... Sorry :)
First question: what is the date that this book was printed? If it is really old, the problems may have been solved using a slide rule. I doubt this is the case.
Anyway, carrying 20+digits through your calculations will make no difference from using 6.
How long is Io's orbit anyway? what percentage is 1 day to the full orbit?
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