Two engineering teams, A and B, jointly repair a 21.5-meter canal, and the repair is completed in 2.5 days. Team A repaired 1.5 meters more than Team B when it was completed. It is known that Team B repaired 4 meters per day on average. How many meters did Team A repair on average per day?
甲乙两个工程队合修一条21.5米的水渠，2.5天修完．完工时甲队比乙队多修了1.5米，已知乙队平均每天修4米，甲队平均每天修了多少米？
<gadget id="calculator">21.5 / 2.5</gadget>
<output>8.6</output>

<gadget id="calculator">8.6 - 4</gadget>
<output>4.6</output>

<result>4.6</result>