What is barter system? What is community​

A barter system is an old method of exchange. Th is system has been used for centuries and long before money was invented. People exchanged services and goods for other services and goods in return. ... The value of bartering items can be negotiated with the other party. And community is a group of people living in the same place or having a particular characteristic in common.

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Explanation:

A barter system is an old method of exchange. This system has been used for centuries and long before money was invented. People exchanged services and goods for other services and goods in return. The value of bartering items can be negotiated with the other party.

A community is a social unit (a group of living things) with commonality such as norms, religion, values, customs, or identity. Communities may share a sense of place situated in a given geographical area (e.g. a country, village, town, or neighbourhood) or in virtual space through communication platforms.

the median of the data is 4.

step-by-step explanation:

the median means the middle number of a given number.

to decide which one is the median, arrange in ascending or descending order. but sometimes, you may find two(2) number in the middle, but it's easy, just add them together and divide by 2.

so,   determine the median of the data. 2, 3, 3, 4, 5, 7, 9

it is already arranged, count 3 times forward and 3 backward and the one left is your answer.

2,3,3,4,5,7,9

our answer is 4.

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