In a school annual day function parade, a group of 1400 students need to march behind the band of 800 members. The two groups have to march in the same number of columns. What is the maximum number of columns in which they can march?
A building is in form of a right circular cylinder and cone as shown in the picture. The radius of cone and cylinder is 3 meters. The height of cylinder and cone are 11.5 meters and 4 meters respectively. Find the outer surface area of the building. (Assume π =
A piggy bank contains ^@12^@ ₫1 coins, ^@14^@ ₫2 coins, ^@35^@ ₫5 coins, and ^@31^@ ₫10 coins. If it is equally likely that one of the coins will fall out when the bank is turned upside down, find the probability the coin falling out will be of value less than ^@₫2^@.