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The perimeter of a rectangle is 42 inches. if the width of the rectangle is 6 inches, what is the length

Maria found the least common multiple of 6 and 15. her work is shown below. multiples of 6: 6, 12, 18, 24, 30, 36, 42, 48, 54, 60, . . multiples of 15: 15, 30, 45, 60, . . the least common multiple is 60. what is maria's error?

Find the dimensions of the circle. area = 64π in.² r= in.