Now there are several cylinders whose base radius and height are both 1 and several cylinders whose base radius and height are both 2, the sum of their volumes is 50π, and the sum of their surface areas is 120π. So how many cylinders are there in total?
今有若干个底面半径和高均为1的圆柱体和若干个底面半径和高均为2的圆柱体，它们的体积和为50π，表面积和为120π．那么一共有多少个圆柱体？
<gadget id="calculator">5 + 10</gadget>
<output>15</output>

<result>15</result>