It is known that ☆+☆+▽+⊙+▽=28, ☆+▽=10, then how much is ☆+⊙+▽=.
已知☆+☆+▽+⊙+▽=28，☆+▽=10，那么☆+⊙+▽=多少．
<gadget id="calculator">28 - 20</gadget>
<output>8</output>

<gadget id="calculator">10 + 8</gadget>
<output>18</output>

<result>18</result>