If the school buys 5 footballs and 6 basketballs, it costs 633 yuan; if it buys 3 footballs and 4 basketballs, it costs 405 yuan. Now buy 15 footballs and 15 basketballs, how much is the total cost?
学校如果买5个足球和6个篮球，需633元；如果买3个足球和4个篮球需405元．现在足球和篮球各买15个，共需多少元．
<gadget id="calculator">633 - 405</gadget>
<output>228</output>

<gadget id="calculator">228 / 2</gadget>
<output>114</output>

<gadget id="calculator">114 * 15</gadget>
<output>1_710</output>

<result>1_710</result>