Column calculation: (5/4) is less than (7/15) of a number (1/2), what is this number?
列式计算：(5/4)比一个数的(7/15)少(1/2)，这个数是多少？
<gadget id="calculator">5 / 4</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(5/4) + (1/2)</gadget>
<output>7/4 = around 1.75</output>

<gadget id="calculator">7 / 15</gadget>
<output>7/15 = around 0.466667</output>

<gadget id="calculator">(7/4) / (7/15)</gadget>
<output>15/4 = around 3.75</output>

<result>15/4 = around 3.75</result>