0.86 is a decimal.
086 = eighty-six
086
Smaller.
terminating decimals and repeating decimals
086 3756829
.086
Two of them are terminating decimals and recurring decimals
terminating decimals non terminating decimals repeating decimals non repeating decimals
6.7,6.8,6.4,5.9
The answer depends on what you wish to do with decimals.
Terminating decimals are decimals that end, such as, 2.384. Non-terminating decimals that don't end, such as, 0.3333333333.......
You need decimals when you measure and fractions. You need decimals, because to measure and fractions. Also, so whole numbers could exist if there are decimals. There will be no math if there's no decimals.