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DL (500+50 = 550)
550 is halfway between 500 and 600
550 plus 500 is 1,050. This equation can be calculated mentally, on a calculator or by using a pen and paper.
540
about 500 - 550
540
550
5500
500
In Roman numerals, M = 500 L = 50 so, ML = 550
550 H.P. and 500 lbs of torque
The halfway point between 500 and 600 is (500 + 600) ÷ 2 = 550