<human>:  The red rope was four times the length of the blue rope. The blue rope was 7 centimeters shorter than the yellow rope. If the 3 ropes had a combined length of 37 centimeters, what was the length of the red rope in centimeters?
<bot>: Define a variable ** Let Y = the length of the yellow rope in centimeters
How long is the blue rope? ** Blue rope = Y - 7
How long is the red rope? ** Red rope = 4 * (Y - 7)
Write an equation ** Y + Y - 7 + 4 (Y - 7) = 37 cm
Simplify ** 6Y - 35 = 37
Simplify ** 6Y = 72
Divide by 6 ** Y = <<12=12>>12 cm
What was the length of the red rope in centimeters? ** The red rope was 20 cm long.
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