There are several red balls and green balls. If some balls are put in the cloth bag, the probability of touching the red ball is (3/8). It is known that 15 red balls are placed, how many green balls are placed?
红球和绿球若干，如果在布袋中放入一些球，要求摸到红球的可能性是(3/8)，已知放了15个红球，放了多少个绿球？
<gadget id="calculator">3 / 8</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">15 / (3/8)</gadget>
<output>40</output>

<gadget id="calculator">40 - 15</gadget>
<output>25</output>

<result>25</result>