Suppose nine school children line up to board a school has. There are 4 girls an
ID: 3402294 • Letter: S
Question
Suppose nine school children line up to board a school has. There are 4 girls and 5 boys. What is the number of ways they could line up: Without any restriction So that 4 girls are first then 5 boys in the line. How many 5-letter words can be made from the word: "SUPER" ? How many 11-letter words can be made from the word: "MATHEMATICS"? Three machines I, II and III manufacture 0.4,0.5 and 0.1 of the total production in a plant, respectively. The percentage of defective items produced by I, II and III is 2%, 4% and 1% respectively. Construct the tree diagram For an item chosen at random. What is the probability that it is defective? What is the probability that the defective item came from machine I?Explanation / Answer
7 )
a) 9 students to arrange
no ofways = 9!
b) 4 girls are first then 5 boys,
no of ways = 4! ( to arrange girls) * 5! (to arrange boys)
8) b) no of 11 letter words (2M 2A 2T I C S H E
11!/(2!2!2!)
9)
prob(defective) = 0.4 * 0.02 + 0.5 * 0.04 + 0.1 * 0.01 = 0.029
Use Baye's theorem
given its defective P(machine1) = 0.4 * 0.02/ 0.029