extended form of decimals
No, decimals are not imaginary numbers. Decimals are a way to represent real numbers, which can include both rational numbers (like 0.5 or 3.75) and irrational numbers (like π). Imaginary numbers, on the other hand, are defined as multiples of the imaginary unit (i), where (i^2 = -1), and they are used to extend the concept of numbers beyond the real number line.
terminating decimals and repeating decimals
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.
3rd. Adding Decimals 5th - Adding and subtracting 6th - Dividing Decimals
terminating decimals repeating decimals
Some decimals are. Counting numbers are a proper subset of decimals.
They are decimals that have equal value.