A photo is 6 cm long and 4 cm wide. After being enlarged proportionally, the length is 13.5 cm. What is the width? (use ratio to solve)
一张相片长6厘米，宽4厘米，按比例放大后，长是13.5厘米，宽应该是多少？(用比例来解)
<gadget id="calculator">6 / 13.5</gadget>
<output>0.444444</output>

<gadget id="calculator">4 / 0.444444</gadget>
<output>9.000009</output>

<result>9.000009</result>