My grandfather is 75 years old this year, my father's age is my grandfather's (3/5), and my age happens to be my father's (4/15), how old am I this year?
爷爷今年75岁，爸爸的年龄是爷爷的(3/5)，而我的年龄恰巧是爸爸的(4/15)，我今年多少岁？
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">4 / 15</gadget>
<output>4/15 = around 0.266667</output>

<gadget id="calculator">75 * (3/5) * (4/15)</gadget>
<output>12</output>

<result>12</result>