rectangular piece of paper with a length of 45 cm and a width of 21 cm should be cut into: several small squares with the same side length and full centimeters, try to make the side length of the small square as large as possible, and there is no surplus, then How many such small squares can be cut out?
现有长为45厘米，宽为21厘米的一个长方形纸片，要剪成：边长相同且为整厘米的若干小正方形，尽量使小正方形的边长尽可能的大，并且没有剩余，那么共能剪出多少个这样的小正方形．
<gadget id="calculator">45 / 3</gadget>
<output>15</output>

<gadget id="calculator">21 / 3</gadget>
<output>7</output>

<gadget id="calculator">15 * 7</gadget>
<output>105</output>

<result>105</result>