The school organized a donation activity. The sixth grade students donated a total of 400 yuan, and the donations of the fifth grade students were 100 yuan less than twice the donations of the sixth grade students. How much does the fifth grade student donate?
学校组织捐款活动，六年级学生共捐款400元，五年级学生的捐款数比六年级级生捐款数的2倍少100元．五年级学生捐款多少元？
<gadget id="calculator">400 * 2</gadget>
<output>800</output>

<gadget id="calculator">800 - 100</gadget>
<output>700</output>

<result>700</result>