Firewall/NAT

i have a question for multi ips
for example:
    wan ip : 192.168.10.10, 192.168.10.60
    lan ip : 172.19.31.0/24
how can i to set from 172.19.31.0/24 client out by 192.168.10.10 or 192.168.10.60
auto choose each 192.168.10.10 or 192.168.10.60 .
thanks every bady for anser the question.

Sounds like you are doing double NAT?  Usually not a great idea.  We need more info.

I don't quite understand the question.  Do you have multiple public IPs or are they private like you gave in example? 

What do you mean by "how can i to set from 172.19.31.0/24 client out by 192.168.10.10 or 192.168.10.60
auto choose each 192.168.10.10 or 192.168.10.60 ."

If you have multiple public IPs that you would like to use for clients on pfSense LAN, you need to use Proxy ARP and 1:1 NAT or some other form of NAT rules.

Aaron