a school has 20 classrooms one-fourth of them are for kinder and first grade. twice as many are for second and third grade. the rest are for fourth and fifth grade. how many fourth and fifth grade classes are there?

a function could be identified in 3 ways either on a chart,graph, or ordered pairs. first a function is that each point has its own. the rule is that there can be many x's to one y but there can not be 2 x's at different y's. so on a graph when you put a straight line through the y's there should be one dot only to be a function.

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