A piece of rectangular paper with a length of 42 cm and a width of 35 cm, cut this paper into small square pieces. How many small squares can be cut to make the square piece of paper as large as possible?
一张长42厘米，宽35厘米的长方形纸，把这张纸剪成正方形小纸片．要使正方形小纸片尽可能的大，可剪多少个小正方形？
<gadget id="calculator">7 * 7</gadget>
<output>49</output>

<gadget id="calculator">35 / 49</gadget>
<output>5/7 = around 0.714286</output>

<gadget id="calculator">42 * (5/7)</gadget>
<output>30</output>

<result>30</result>