Unity Hope Primary School saved 140 tons of water in the first 4 days of early March, and an average of 35 tons of water per day in the last 6 days. How many tons of water did the Unity Hope Primary School save on average per day in early March?
团结希望小学三月上旬前4天节约用水140吨，后6天平均每天节约用水35吨．团结希望小学三月上旬平均每天节约用水多少吨？
<gadget id="calculator">35 * 6</gadget>
<output>210</output>

<gadget id="calculator">140 + 210</gadget>
<output>350</output>

<gadget id="calculator">350 / 10</gadget>
<output>35</output>

<result>35</result>