In a football tournament at group stage there are five football teams in a group, Brazil, England, Scotland, Argentina and France. Each team plays every other team in their group. There are ten matches altogether. Two teams are picked at random to play the first match. Work out the probability that the first game will be played by a European team and a South American team.

An office supply company conducted a survey before marketing a new paper shredder designed for home use. in the survey, 80 % of the people who tried the shredder were satisfied with it. because of this high satisfaction rate, the company decided to market the new shredder. assume that 80 % of all people are satisfied with this shredder. during a certain month, 100 customers bought this shredder. find the probability that of these 100 customers, the number who are satisfied is 69 or fewer.