Liangliang and Honghong set off from villages A and B at the same time and head towards each other. The speed ratio between Liangliang and Honghong is 4:3. It took Liangliang 30 minutes to go from village A to village B. Ask Honghong to go to village A. How long has it been?
亮亮和红红同时从甲、乙两个村子出发，相向而行，亮亮和红红的速度比是4：3，亮亮从甲村到乙村用了30分钟，求红红到甲村用了多长时间？
<gadget id="calculator">30 / 4</gadget>
<output>15/2 = around 7.5</output>

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

<result>45/2 = around 22.5</result>