First pour 7.8 liters out of a barrel of gasoline, then pour out 5.65 liters, leaving 2.34 liters. How many liters of gasoline are there in total?
一桶汽油先倒出7.8升，再倒出5.65升，还剩下2.34升，这通汽油一共有多少升？
<gadget id="calculator">7.8 + 5.65 + 2.34</gadget>
<output>15.79</output>

<result>15.79</result>