Xiao Ming's father likes to collect stamps. 20% of the stamps he collects are about operas, and 30% are about calligraphy and painting. There are 175 stamps of these two kinds. How many stamps did Xiao Ming's father collect in total?
小明的爸爸喜欢集邮，他收集的邮票中有20%是关于戏曲的，有30%是关于书法和绘画的，这两种邮票一共有175张，小明的爸爸共收集了多少张邮票．
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">(1/5) + (3/10)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">175 / (1/2)</gadget>
<output>350</output>

<result>350</result>