60 cm long aluminum wires are used to form a rectangular parallelepiped frame with a length of 7 cm and a height of 5 cm. What is the maximum width of this frame in cm?
用60厘米长的铝线围成一个长方体框架，长7厘米，高5厘米，这个框架的宽最多是多少厘米．
<gadget id="calculator">60 / 4</gadget>
<output>15</output>

<gadget id="calculator">7 + 5</gadget>
<output>12</output>

<gadget id="calculator">15 - 12</gadget>
<output>3</output>

<result>3</result>