((1/30)+(1/45)+(1/60))*(15/7).
((1/30)+(1/45)+(1/60))*(15/7)．
<gadget id="calculator">1 / 30</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">1 / 45</gadget>
<output>1/45 = around 0.022222</output>

<gadget id="calculator">1 / 60</gadget>
<output>1/60 = around 0.016667</output>

<gadget id="calculator">(1/30) + (1/45) + (1/60)</gadget>
<output>13/180 = around 0.072222</output>

<gadget id="calculator">15 / 7</gadget>
<output>15/7 = around 2.142857</output>

<gadget id="calculator">(13/180) * (15/7)</gadget>
<output>13/84 = around 0.154762</output>

<result>13/84 = around 0.154762</result>