According to incomplete statistics, among the foreign friends visiting Xi'an Expo, men accounted for about 3/10 of all visitors, and women accounted for 1/10. What percentage of foreign friends are males more than females in all visitors?
据不完全统计，参观西安世园会的外国朋友中，男性大约占所有参观人数的(3/10)，女性占(1/10)．外国朋友中男性比女性多占所有参观人数的几分之几？
<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(3/10) - (1/10)</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>