The field of economics is broken down into two distinct areas of study: microeconomics and macroeconomics. Microeconomics looks at the smaller picture and focuses more on basic theories of supply and demand and how individual businesses decide how much of something to produce and how much to charge for it. Macroeconomics, on the other hand, looks at the big picture (hence "macro"). It focuses on the national economy as a whole and provides a basic knowledge of how things work in the business world.
Microeconomics/ Macroeconomics and Managerial Economics have plenty in common. They all overlap in some form or fashion. Managerial economics is applied theory. Much of managerial economics applies the theories set forth in microeconomic theory. The relationship between the Microeconomics and the Macroeconomics are based on the result of choices made by each household and firms and some models of macroeconomics especially while originating the collective of production and consumption levels among both the branches of economics.