An instant noodle factory wants to produce a batch of instant noodles for children in the earthquake-stricken area. The first half of the month completed the plan (3/5), and the second half of the month completed the plan (2/3). How much of the plan was exceeded?
某方便面厂要为地震灾区的小朋友生产一批方便面．上半月完成了计划的(3/5)，下半月完成了计划的(2/3)．超额完成了计划的几分之几？
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">(2/3) - 1</gadget>
<output>-1/3 = around -0.333333</output>

<gadget id="calculator">(3/5) + (-1/3)</gadget>
<output>4/15 = around 0.266667</output>

<result>4/15 = around 0.266667</result>