Xiao Ming spent 45 minutes doing his homework yesterday, including (1/5) hour for math homework, (1/4) hour for Chinese homework, and the rest of the time for English. How many hours did he spend on English homework?
昨天小明做作业用了45分钟，其中做数学作业用了(1/5)小时，做语文作业用了(1/4)小时，余时间做英语，英语作业用了多少小时？
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(3/4) - (1/5) - (1/4)</gadget>
<output>3/10 = around 0.3</output>

<result>3/10 = around 0.3</result>