Final answer:
The decimal 4.01 is equivalent to the mixed number 4 1/100, which is already in its simplest form.
Step-by-step explanation:
To convert the decimal 4.01 to a mixed number in simplest form, we need to separate the number into its whole and fractional parts. The whole number part is '4', and the decimal part is '.01'. To convert '.01' into a fraction, we note that '.01' is the same as '1/100' because it represents one hundredth.
The mixed number is therefore 4 and 1/100. However, this fraction cannot be simplified further since '1' is already the smallest whole number numerator possible with respect to the denominator '100'. So, the mixed number in simplest form is 4 1/100.