mysql中两个count值相除，如何合并？

Question

如何合并如下两条语句实现两个结果相除保留2位小数的百分比。
语句1:
select count(id) as total_pass from table1 where status = 'pass' group by orderid，product
语句2：
select count(sn) as total_sn from table1 group by group by orderid，product
实现结果：
orderid | product | total_pass | total_sn | rate
201 | 产品A | 50| 50| 100.00%
203 | 产品B | 60| 120 | 50.00%