Computer science question?

Question

if your modem uses 802.11b and router uses 802.11g what happens?

Answer 1

Most 802.11g devices will also speak 802.11b.  Two wireless devices, when they initially start taking to each other go through some "handshaking".  In these initial exchanges, each device will say what protocols it supports, and they will sync up to the fastest speed that both devices support (in this case, "b").

Answer 2

Slower speeds.