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How many $20 bills do you need to have to make $280

Maurice has 54 fewer comic books than rebecca.they have 130 comic books together .how many comic books are in maurices collection ? how many comic books are in rebeccas collection

Afarmer has a large field that is x feet in length. he wants to fence in a rectangular section in the middle of the field , leaving a length of 100 feet of open field behind each end of the fenced rectangle.he also wants the width of the fenced-in space to be 100 feet less than its length. find the expressions to represent the length and width of the fenced section of the field