classroom is 80 decimeters long and 64 decimeters wide. The floor is paved with self-made square cement boards. The number of cement boards used must be an integer. Each cement board should be as large as possible. How many such cement boards are needed in total? ?
一间教室长80分米，宽64分米，用自制的正方形水泥板铺地，要求使用水泥板的块数必须是整数，每块水泥板要尽可能大，共需这样的水泥板多少块？
<gadget id="calculator">16 * 16</gadget>
<output>256</output>

<gadget id="calculator">64 / 256</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">80 * (1/4)</gadget>
<output>20</output>

<result>20</result>