Among the five fractions (9/20), (4/12), (7/17), (18/45), and (30/25), how many fractions can be reduced to finite decimals?
(9/20)、(4/12)、(7/17)、(18/45)、(30/25)五个分数中，能化成有限小数的分数有多少个
<gadget id="calculator">12 / 4</gadget>
<output>3</output>

<gadget id="calculator">3 / 1</gadget>
<output>3</output>

<result>3</result>