180dwt是多少g？
180dwt = 279.9313g
是279.9313g，所以说成280g也没问题——四舍五入的误差在0.5%以内。
反过来，180g是多少dwt？
180g = 115.7427dwt
计算公式: g = dwt × 1.555174
该数值前后的 dwt → g
90 dwt139.9656g
100 dwt155.5174g
110 dwt171.0691g
120 dwt186.6209g
130 dwt202.1726g
140 dwt217.7243g
150 dwt233.2761g
160 dwt248.8278g
170 dwt264.3796g
180 dwt279.9313g
190 dwt295.483g
200 dwt311.0348g
210 dwt326.5865g
220 dwt342.1382g
230 dwt357.69g
240 dwt373.2417g
250 dwt388.7935g
260 dwt404.3452g
270 dwt419.8969g
280 dwt435.4487g