The idea is simple: apart from regular numbers (like 4, 3.14 or 43942), you can also input ranges (like 4~6, 3.1~3.2 or 40000~45000). The character between the two extremes of the range is a tilde (~), a little wave symbol. You can find it on most keyboards, but for convenience, I also included it in the keypad above. The range notation says the following to the calculator: I am not sure about the exact number here, but I am 95% sure it’s somewhere in this range.

source: L