Mom bought 2.5kg of apples and 3kg of bananas from the fruit shop. It is known that apples are 12 yuan per kilogram and bananas are 6.8 yuan per kilogram. How much did mother spend on these two fruits?
妈妈从水果店买回2.5千克苹果和3千克香蕉．已知苹果每千克12元，香蕉每千克6.8元．妈妈买这两种水果共花了多少元钱？
<gadget id="calculator">12 * 2.5</gadget>
<output>30</output>

<gadget id="calculator">6.8 * 3</gadget>
<output>20.4</output>

<gadget id="calculator">30 + 20.4</gadget>
<output>50.4</output>

<result>50.4</result>