A conference hall is a rectangle measuring 70 cm long and 50 cm wide. If you want to lay square floor tiles of the same size, you must lay the whole piece of the ground, how long should you choose?
一个会议厅是一个厂70厘米、宽50厘米的长方形．如果要铺上同样大小的正方形地板砖必须整块整块地铺，应选择边长是多大的地板砖？
<gadget id="calculator">2 * 5</gadget>
<output>10</output>

<result>10</result>