Students in two classes in the fifth grade collected tree species. Class 1 had 46 students, and each person collected 0.14 kilograms. Class 2 had 36 students who collected a total of 6.15 kilograms. How many kilograms of tree species were collected by the two classes?
五年级两个班的学生采集树种，1班46人，每人采集0.14千克，2班36人共采集6.15千克，两个班一共采集树种多少千克？
<gadget id="calculator">46 * 0.14</gadget>
<output>6.44</output>

<gadget id="calculator">6.44 + 6.15</gadget>
<output>12.59</output>

<result>12.59</result>