What is 3.84, 3.789, 3, 3 41/50 from greatest to least

The arrangement of the numbers from the greatest value to the least in value will be the following respectively,

1. 3.84
2. 3 41/50 ~ 191/50 ~ 3.82
3. 3.789
4. 3    

Decimals are just the same in arranging real numbers, regardless whether descending or ascending. 1, 2 , 3 and so on.
These arrangements are important in order to understand the system and fluctuation of numbers every now and then. This will also influence more complex and perplex expressions such as integrating basic properties and operations and also, variables to find the unknowns. Integers too.

Some of her  assignments would be creation of drugs. she is a medical chemist after all so she'd need to have the necessary knowledge to make medicine which can later be sold in a pharmacy