The two wheels of A and B roll from A to B at the same time. A turns 4800 times, and the number of turns of B is A (3/4). If the circumference of A is 31.4 cm less than that of B, the radius of B How many centimeters is it?
甲乙两个车轮同时从A地滚到B地，甲轮转了4800圈，乙轮转的圈数是甲的(3/4)，如果甲轮的周长比乙轮少31.4厘米，乙轮的半径是多少厘米？
<result>20</result>