Students from two classes in the fifth grade participated in the tree species collection activity. The first class had 43 students, each of whom collected an average of 0.16 kilograms, and the second class had 39 students, who collected a total of 6.48 kilograms. How many kilograms of tree species were collected by the two classes?
五年级两个班的学生参加采集树种活动，一班43人，平均每人采集了0.16千克，二班39人，共采集6.48千克，两个班一共采集树种多少千克？
<gadget id="calculator">0.16 * 43</gadget>
<output>6.88</output>

<gadget id="calculator">6.88 + 6.48</gadget>
<output>13.36</output>

<result>13.36</result>