It cost a total of 740 yuan to buy 3 basketballs and 4 footballs, and a total of 980 yuan to buy 5 basketballs and 4 footballs. How much is a basketball?
学样买3个蓝球和4个足球共花了740元，买5个蓝球和4个足球共花了980元，一个蓝球多少元？
<gadget id="calculator">980 - 740</gadget>
<output>240</output>

<gadget id="calculator">5 - 3</gadget>
<output>2</output>

<gadget id="calculator">240 / 2</gadget>
<output>120</output>

<result>120</result>