On average, the canteen needs 3 bags of rice per week. Originally there were 36 bags, but another 42 bags were shipped. How many weeks can these rice be eaten.
食堂平均每周需要3袋大米．原有36袋，又运来42袋．这些大米能吃多少周．
<gadget id="calculator">36 + 42</gadget>
<output>78</output>

<gadget id="calculator">78 / 3</gadget>
<output>26</output>

<result>26</result>