If 4.5, 7.5, (1/2) and (3/10) are used as a ratio, what is the product of the inner terms?
把4.5、7.5、(1/2)、(3/10)组成比例，其内项的积为多少
<gadget id="calculator">7.5 * 0.3</gadget>
<output>2.25</output>

<result>2.25</result>