Xinhua Farm has built a 7.5-kilometer-long canal for 4 days, 0.65 kilometers per day, and the rest will take 7 days to complete. How many miles per day on average?
新华农场修一条长7.5千米的水渠，已经修了4天，每天修0.65千米，剩下的要7天修完．平均每天修多少千米？
<gadget id="calculator">0.65 * 4</gadget>
<output>2.6</output>

<gadget id="calculator">7.5 - 2.6</gadget>
<output>4.9</output>

<gadget id="calculator">4.9 / 7</gadget>
<output>0.7</output>

<result>0.7</result>