In this case you would have numbers that are not whole, so you have decimals.
Ex of how you estimate numbers:
5.45 estimate is 5
3.20 estimate is 3
7.50 estimate is 8
1.89 estimate is 2
Everything that is beyond .50 decimals is rounded up to the next no. 7.50 is estimated to 8 because the decimals are .50 or above. Same goes for the other ex. 1.89 which will become 2.
Everything that is under the .50 decimals we rounded down to the same number, 5.45 has the decimals under .50 that means that the number is rounded down to 5. same applies to 3.20 which will become 3.
Hope you understand the explanation!
Cheers
