Guys, you are missing one point here.
Both calculators are made by Casio, so they should work with the same rules and thus, displaying the same result.
As for who is right or wrong, the formula is wrong as it doesn't state what's first. It lacks a pair of parentheses.
And I agree with THE1, back on-topic:
Please excuse my bad English.
Currently gaming on a PC with an i5-4670k@stock (for now), 16Gb RAM 1600 MHz and a GTX 1070
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