There are two piles of apples. After pile A transports 2.48 tons to pile B, pile B is 0.9 tons more than pile A. How many tons more pile A is than pile B.
两堆苹果，甲堆运2.48吨给乙堆后，乙堆比甲堆多0.9吨，原来甲堆比乙堆多多少吨．
<result>4.08</result>