Explanation on what buying on margin means ?

Margin is the difference between the purchase and sale price of goods.

Explanation:

It is a trade term expressed in percentages. It can also mean the difference between the same goods in a different market. The margin represents almost all differences and oscillations in the prices of one commodity. Therefore, the margin implies a difference in the value of exchange rate securities on different stock exchanges. In commercial companies, the margin is the basic element that determines the price adjusted to market conditions.

its main object was the establishment of "settlement houses" in poor urban areas, in which volunteer middle-class "settlement workers" would live, hoping to share knowledge and culture with, and alleviate the poverty of, their low-income neighbors.

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