ball of wool, 15 meters and 8 decimeters are used, and the used one is 9.2 meters longer than the rest. How many meters is this ball of wool originally?
一团毛线，用去15米8分米，用去的比剩下的长9.2米，这团毛线原来长多少米？
<gadget id="calculator">15.8 - 9.2</gadget>
<output>6.6</output>

<gadget id="calculator">15.8 + 6.6</gadget>
<output>22.4</output>

<result>22.4</result>