Most people do not use it in their daily lives.
You and I use it every day, and have done all our lives.
Melvil Dewey created the Dewey Decimal system. It is a classification system used by libraries, and not what is meant in the question. The decimal number system is the number system that we all use on a daily basis; it was invented by a succession of Arab and Hindu mathematicians beginning about 1400 years ago.
It is the number system we use everyday.
If you mean pie: it is eaten. If you mean the number pi: It is used in all sorts of situations. Whether you use it in "real life situation" mainly depends whether you work in engineering. Most people won't use the number pi in their daily lives.
Children can use multiplication in their daily lives in a number of creative ways. A child can calculate how many times they eat in a week for fun for example.
we can use music in our daily lives by setting the mood
Eating
We breathe it.
negotiation
In a sale,
temperature,money(withdrawing&depositing in a bank),and most numbers the are on a number line.
Technology
money uses decimals
money, medicine
Nowadays the whole world uses the same number system - decimal for daily use and (essentially) binary for electronic and optical data storage and processing.
Most people do not use it in their daily lives.