Why did python add 1 at the end? console.log(9.89+3.48) = 13.37000000000001

Question

https://i.stack.imgur.com/4AwjX.png

Its adding in 1 at the end of that console log output. Why? Answer is suppose to be only 13.37

I’m pretty sure it’s not python, from the look of the screenshot, it’s node js? — Taku, Sep 22 '17 at 20:28
Thats correct sir, its javascript. It was a trick question. Why does javascript add 1 at the end though? — Uros Tadic, Sep 22 '17 at 20:30

score 1 · Accepted Answer · answered Sep 22 '17 at 20:29

1

Likely because it is adding to numbers of type double (I am not a huge Python expert though, so I could be wrong). The doubletype, much like single does not have perfect precission. Hence some decimal errors can occur...

answered Sep 22 '17 at 20:29

Jakob Busk Sørensen

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In python it's `float` not `double` but the principle is the same :) – roganjosh Sep 22 '17 at 20:31

Why did python add 1 at the end? console.log(9.89+3.48) = 13.37000000000001

1 Answers1