Xiaobing bought a fountain pen and a ballpoint pen. The unit price of the pen is 13.56 yuan, and the unit price of the ballpoint pen is 3.79 yuan. How much did Xiaobing spend in total?
小兵买了一支钢笔和一支圆珠笔，钢笔的单价是13.56元，圆珠笔的单价是3.79元，小兵一共花了多少元？
<gadget id="calculator">13.56 + 3.79</gadget>
<output>17.35</output>

<result>17.35</result>