Among (3/7), (3/13), (7/20), (15/22), (18/29), how many can be converted into finite decimals?
在(3/7)、(3/13)、(7/20)、(15/22)、(18/29)中，能化成有限小数的是多少．
<gadget id="calculator">7 / 20</gadget>
<output>7/20 = around 0.35</output>

<result>7/20 = around 0.35</result>