The difference between 4 times x minus 6 is 54, then x=how much.
x的4倍减去6的差是54，则x=多少．
<gadget id="calculator">54 + 6</gadget>
<output>60</output>

<gadget id="calculator">60 / 4</gadget>
<output>15</output>

<result>15</result>