Li Hua and Zhang Ming set off from villages A and B at the same time respectively, walking toward each other, and met at a distance of 15 kilometers from the midpoint of the two villages. Li Hua's speed is 40% of Zhang Ming's speed, find the distance between the two villages.
李华和张明分别从A、B两村同时出发，相向而行，在距两村中点15千米相遇．李华的速度是张明速度的40%，求两村之问的距离．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">2 + 3</gadget>
<output>5</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(1/2) - (2/5)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">15 / (1/10)</gadget>
<output>150</output>

<result>150</result>