Unable to ping from Terminal but able to browse using firefox?

Q: Unable to ping from terminal but able to browse the internet with browsers ?

Symptoms :
ping 192.168.1.1 ----- works

ping google.com
connect : Network is unreachable

traceroute -n www.google.com
traceroute to www.google.com (66.102.9.147), 30 hops max, 40 byte packets
connect: Network is unreachable.

netstat -nr
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
10.51.0.0 0.0.0.0 255.255.0.0 U 0 0 0 wlan0
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 wlan0

Ans : The system does not have a default route.

to add a default route: route add default gw 192.168.1.x (where x is the ip of the gateway)

For more information on adding a default route to the system read this