1. 8 red card number 1-8 put in one box, 8 blue card number 1-8,put in another box, take one card from each of the box,what is the probability that the number match each other?
2. There are 60 cars in the rental place, 31 white, 19 red and 10 blue. they can be full size, medium or economic cars. How many white cars are full size?
条件1:all medium and economic cars are NOT full size
条件2:the total of full size is equal to the sum of medium and economic cars.