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Gregory draws a scale drawing of his room. the scale that he uses is 1 cm : 4 ft. on his drawing, the room is 3 centimeters long. which equation can be used to find the actual length of gregory's room?

45% of the trees in a park are apple trees. there are 27 apple trees in the park. how many trees are in the park in all?

3x = 729 solve for x plz . it's urgent. will mark