Guangming Primary School held a sports meeting. There are 70 people in the third grade participating in the competition, and the number of participating in the fourth grade is 5 times less than that of the third grade, which is exactly three times that of the fifth grade. How many people in the fifth grade participate in the competition?
光明小学举行运动会．三年级有70人参加比赛，四年级参加的人数比三年级的2倍少5人，正好是五年级的3倍，五年级参加比赛有多少人？
<gadget id="calculator">70 * 2</gadget>
<output>140</output>

<gadget id="calculator">140 - 5</gadget>
<output>135</output>

<gadget id="calculator">135 / 3</gadget>
<output>45</output>

<result>45</result>