[Refer " How to calculate LCM and HCF of Decimals " here]

Step 1: Make the same number of decimal places in all the given numbers by suffixing

zero(s) in required numbers as needed.

=> 2.04, 0.24 and 0.80

Step 2: Now find the HCF of these numbers without decimal.

=> HCF of 204, 24 and 80 = 4

Step 3: Put the decimal point in the result obtained in step 2 leaving as many digits on its

right as there are in each of the numbers.

i.e., here we need to put decimal point in the result obtained in step 2 leaving two digits

on its right.

=> HCF of 2.04, 0.24 and 0.8 = 0.04