Why 0.1 + 0.2 = 0.30000000000000004 ? Java script

Question

var num1 = 0.1 , num2 = 0.2 , num3 = 0.3 ;
console.log (num1 + num2 == num3 ) ;
false !!!!!! because 0.1 + 0.2 = 0.300000004
somebody explain why 🤔🤔🤔

Answer 1

because it is irrational. computer can never display exact numbers when working with decimals even if you add seemingly rational decimals like 0.1. reason is that there is always a certain degree of uncertainty and computer can't represent float point exactly. try setting an epsilon for tolerance and rounding the number within the epsilon range. this is especially important when using == to compare two float point numbers