Determine Whether the Sequence $3,9,15,21 , \ldots$ Is Arithmetic

question 95

Essay

Determine whether the sequence $3,9,15,21 , \ldots$ is arithmetic. If it is arithmetic, find the common difference.

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Definitions:

Unit Of Account

A common unit for measuring the value of each good or service.

Store Of Value

Anything that retains its purchasing power over time.

Double Coincidence

Double Coincidence is a term used in economics to describe a situation where two parties each hold an item the other wants, allowing for an exchange without the need for a common medium of trade, like money.

Barter System

An ancient method of exchange where goods and services are traded directly for other goods and services without using money.