The fourth-grade students collected tree species. The first group collected 1.28 kilograms, the second group collected 0.95 kilograms, and the third group collected 0.68 kilograms less than the total number of the first and second groups. How many kilograms of tree species did the third group collect?
四年级同学采集树种，第一小组采集1.28千克，第二小组采集0.95千克，第三小组采集的树种比第一、二组的总数少0.68千克，第三小组采集树种多少千克？
<gadget id="calculator">0.95 - 0.68</gadget>
<output>0.27</output>

<gadget id="calculator">1.28 + 0.27</gadget>
<output>1.55</output>

<result>1.55</result>