A grid with three rows and fifty two columns is tiled with 78 identical 2*1 tiles. How many ways can the grid be tiled so that exactly 2 tiles are vertical?
Few teams of boys and girls are made separately. Each team of girls has 15 members. All teams of boys have same numbers of members that is more than 5. The total number of team members is 80. Which of the following numbers cannot be the number of members in a team of boys? A 7 B 10 C 15 D 25