Passage: Early attempts to land tanks for close support and to get past the sea wall failed when the LCM landing craft carrying them hung up behind the reef. Some of these craft were hit out in the lagoon while they waited to move in to the beach and either sank outright or had to withdraw while taking on water. Two Stuart tanks were landed on the east end of the beach but were knocked out of action fairly quickly. The battalion commander of 3rd Battalion, 2nd Regiment found several LCMs near the reef and ordered them to land their Sherman tanks and head to Red Beach 2. The LCMs dropped ramps and the six tanks came down, climbed over the reef and dropped into the surf beyond. They were guided in to shore by Marines on foot, but several of these tanks fell into holes caused by the naval gunfire bombardment and sank. The surviving Shermans on the western end of the island proved considerably more effective than the lighter Stuarts. They helped push the line in to about 300 yards (270 m) from shore. One became stuck in a tank trap and another was knocked out by a magnetic mine. The remaining tank took a shell hit to its barrel and had its 75 mm gun disabled. It was used as a portable machine gun pillbox for the rest of the day. A third platoon was able to land all four of its tanks on Red 3 around noon and operated them successfully for much of the day, but by day's end only one tank was still in action.

Question: How many tanks was the third platoon able to land?
four