The ratio of volleyballs to footballs in the school gym room is 2:3, and the ratio of footballs to basketballs is 4:5. It is known that there are 100 footballs and volleyballs. How many more basketballs are there than footballs?
学校体育室排球与足球个数的比是2：3，足球与篮球个数的比是4：5，已知足球与排球共有100个，求篮球比足球多多少个？
<gadget id="calculator">2 + 3</gadget>
<output>5</output>

<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">100 * (3/5)</gadget>
<output>60</output>

<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">60 / (4/5)</gadget>
<output>75</output>

<gadget id="calculator">75 - 60</gadget>
<output>15</output>

<result>15</result>