Our school originally planned to use 180 tons of coal per month, but the actual monthly saving is (2/15) lower than the plan. How many tons of coal is actually used per month?
我们学校原计划每月用煤180吨，实际每月比计划节约(2/15)，实际每月用煤多少吨？
<gadget id="calculator">2 / 15</gadget>
<output>2/15 = around 0.133333</output>

<gadget id="calculator">1 - (2/15)</gadget>
<output>13/15 = around 0.866667</output>

<gadget id="calculator">180 * (13/15)</gadget>
<output>156</output>

<result>156</result>