select
exp_type,
round(avg(timestampdiff(minute,out_time,in_time)/60),1) as time
from exp_action_tb e1
join express_tb e2 on e1.exp_number=e2.exp_number
group by exp_type
order by time;

select
exp_type,
round(avg(timestampdiff(minute,out_time,in_time)/60),1) as time
from exp_action_tb e1
join express_tb e2 on e1.exp_number=e2.exp_number
group by exp_type
order by time;