Guangming Primary School held a calligraphy and painting competition to welcome June 1st. The number of girls participating in the competition was 15 more than that of boys. As a result of the competition, all boys will win prizes, and the number of boys and girls will be equal. It is known that the number of girls who have won awards accounts for 70% of the total number of girls. How many boys participated in the competition?
光明小学举行迎六一书画比赛，参加比赛的女生比男生多15人．比赛结果，男生全部获奖，且男、女生获奖的人数相等．已知获奖的女生人数占女生总人数的70%，参加比赛的男生共有多少人？
<gadget id="calculator">70 / 100</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">1 - (7/10)</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">15 / (3/10)</gadget>
<output>50</output>

<gadget id="calculator">50 - 15</gadget>
<output>35</output>

<result>35</result>