The fruit shop shipped 12 boxes of apples and 18 boxes of bananas. Each box of the two fruits weighs 15 kg. How many kilograms did the apples and bananas weigh together?
水果店运来苹果12箱，香蕉18箱．两种水果每箱都重15千克．运来的苹果和香蕉一共重多少千克？
<gadget id="calculator">12 + 18</gadget>
<output>30</output>

<gadget id="calculator">30 * 15</gadget>
<output>450</output>

<result>450</result>