A total of 15 kilograms of rice and flour were bought from the store, and rice accounted for (3/4). Later, some flour was bought, and rice accounted for (1/2) of the total weight. How many kilograms of flour did you buy back later?
商店买回大米和面粉共15千克，大米占(3/4)，后来又买了一些面粉，这时大米占总重量的(1/2)．后来买回的面粉是多少千克？
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(3/4) / (1/2)</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">15 * (3/2)</gadget>
<output>45/2 = around 22.5</output>

<gadget id="calculator">(45/2) - 15</gadget>
<output>15/2 = around 7.5</output>

<result>15/2 = around 7.5</result>