Hongkong Cab

We will go to Hongkong on May 19-23, 2013 and we are 4 adults and 1 child. We will stay at IBIS HK Central & Sheung Wan Hotel. If we take a cab from the airport to our hotel, how much will it cost us? Since we are 4 adults and 1 child, can we be accomodated in one cab? Will they charged us individually or charged us as one way trip together? Thanks.