The second class of the fifth grade bought 2 footballs and 30 skipping ropes, paid 200 yuan, and got 15 yuan back. 40 yuan per football, how much is each skipping rope? (solution by equation)
五年级二班买来2个足球和30根跳绳，付出200元，找回15元．每个足球40元，每根跳绳多少元？(用方程解)
<gadget id="calculator">40 * 2</gadget>
<output>80</output>

<gadget id="calculator">200 - 80 - 15</gadget>
<output>105</output>

<gadget id="calculator">105 / 30</gadget>
<output>7/2 = around 3.5</output>

<result>7/2 = around 3.5</result>