There are two piles of coal, pile A has 4.5 tons, pile B has 6 tons, pile A uses 0.36 tons every day, pile B uses 0.51 tons every day. After how many days are the two piles left with equal tons?
两堆煤，甲堆有4.5吨，乙堆有6吨，甲堆每天用去0.36吨，乙堆每天用去0.51吨．几天后两堆剩下的吨数相等？
<gadget id="calculator">6 - 4.5</gadget>
<output>1.5</output>

<gadget id="calculator">0.51 - 0.36</gadget>
<output>0.15</output>

<gadget id="calculator">1.5 / 0.15</gadget>
<output>10</output>

<result>10</result>