The wheel of car A rotates once and the length of the wheel imprint on the ground is 90 cm. The wheel of car B turns 120 degrees and the length of the wheel imprint is 20 cm. Then, how many times the diameter of the wheel A is the diameter of the wheel B.
甲车的车轮转动一周在地上的车轮印痕长为90厘米，乙车的车轮转120度，车轮印痕长为20厘米，那么，甲车轮直径是乙车轮直径的多少倍．
<result>1.5</result>