12 also intended to have a A$250,000 prize, but tasks and challenges during both seasons resulted in the prize decreasing. In Big Brother 11, the final prize was A$200,000 and in Big Brother 12 the prize was $234,656. In Big Brother 4, the prize money was a guaranteed A$1,000,000. In Big Brother 5 and Big Brother 6 continued to offer the A$1,000,000, but introduced a fine system. The winner of Big Brother 5 received $836,000, while the winner of Big Brother 6 received $426,000. Big Brother 7 was advertised as having no prize money. When the series began, it was revealed the grand prize would be based on the Household's completion of weekly tasks. The money earned for the grand prize was $450,000. In both celebrity spin-offs, Celebrity Big Brother Australia and Big Brother VIP Australia, the winner was awarded $100,000 to the charity of their choice. Tasks & Missions During their time in the house, housemates are given tasks by Big Brother. Punishments Big Brother 5 introduced a fines system in which the $1,000,000 cash prize was decreased by $5,000 each time housemates violated a rule of Big Brother. The house used for the 6th season featured a Punishment Room, where housemates would sometimes be sent to be punished in addition to the $5,000 fine. In Big Brother 7, some changes were made. These monetary fines were subtracted from the household budget rather than from the prize money, while the Punishment Room remained. In Big Brother 9 there was a small, rectangular-shaped room, linked to the lounge. This room was the Naughty Corner. This room was similar to the Punishment Room of the sixth and seventh series. The eighth and ninth series' featured no fines system at all. Instead, Big Brother used the original striking system more frequently that meant when a housemate received three strikes they were evicted. Intruders Most seasons of Big Brother Australia usually includes "Intruders". Intruders are new housemates added to the house by the show's producers as ongoing housemates after the series has started. Intruders will be eligible to win the series but will often face a special "Intruder Eviction" shortly after their entrance to the house (either by House Vote, Australia's vote or some combination of both). Big Brother in Australia Network Ten iteration (2001–08) The first Australian series began to broadcast on 23 April 2001. It was hosted by Gretel Killeen from