Soup cans are stacked in a pyramid so that a row always has one less can than the row below it. For example- 6 cans would be stacked in 3 rows: a row of 3 cans, a row of 2 cans, and a row of 1 can. In order to maximize space, the manager of the grocery store wants to stack soup cans until there are at least 15 soup cans in one pyramid. However, if there are more than 30 soup cans she's afraid the pyramid might fall. How many cans of soup can be in the pyramid?
What if the manager wanted to stack 10 rows of soup cans? 100? Can you write a formula to generalize how many cans are needed for a pyramid that is n rows?
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