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a = 175.8 $B!!!J@h!9=5!K(B
b = 192.5 $B!!!J@h=5!K(B
c = 205.1 $B!!!J:#=5!K(B

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d = c + b − a = 205.1 + 192.5 − 175.8 = 221.8

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d = c + (b − a) = 205.1 + (192.5 − 175.8) = 221.8

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d = b + (c − a) = 192.5 + (205.1 − 175.8) = 221.8

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d = c + {(b − a) + (c − b)}/2 = 205.1 + {(192.5 − 175.8) + (205.1 − 192.5)}/2 = 219.75

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