The parent is referring to an interval, since floating point is essentially a disguised interval arithmetic. For IEEE754 64-bit doubles, the interval containin

The parent is referring to an interval, since floating point is essentially a disguised interval arithmetic. For IEEE754 64-bit doubles, the interval containing 0.1 is: [0.099999999999999991673327315311, 0.100000000000000005551115123126]