delivery truck loaded with 500 cartons of milk, after being delivered to 15 retail outlets, left 35 cartons. How many boxes are delivered per retail location on average?
一辆送货车装了500箱牛奶，送到15个零售点后，还剩下35箱．平均每个零售点送了多少箱？
<gadget id="calculator">500 - 35</gadget>
<output>465</output>

<gadget id="calculator">465 / 15</gadget>
<output>31</output>

<result>31</result>