shell求两个数相除后的百分比

#!/bin/bash
a=38
b=99

percent_1=$(printf "%d%%" $((a*100/b)))
# 或者
percent_2=`awk 'BEGIN{printf "%.1f%%\n",('$a'/'$b')*100}'`
# 保留１位小数,四舍五入
echo $percent_1
echo $percent_2

percent_1=38%
percent_2=38.4%