Question

5. A survey of top executives revealed that 15% of them regularly read Time magazine, 25% read Newsweek, and 50% read U.S. News & World Report. Five percent read both Time and U.S. News & World Report. What is the probability that a particular top executive reads either Time or U.S. News & World Report regularly?

6. A study by the National Park Service revealed that 75% of the vacationers going to the Rocky Mountain region visit Yellowstone Park, 30% visit the Grand Tetons, and 25% visit both. What is the probability that a vacationer will visit at least one of these magnificent attractions?

7. A lamp manufacturer designed six lamp bases, two lampshade and four patterns that could be used together. How many different arrangements of base, lampshade, and patterns can be offered?

8. If one selects five cards from a standard deck of cards without replacement,

(8a) How many permutations are possible?

(8b) How many combinations are possible?

Answer 1

5)

let people who read time magazine; read newsweek and US news and world report are A,B and C

probability that a particular top executive reads either Time or U.S. News & World Report regularly

=P(A u C) =PA)+P(C)-P(A n C)=0.15+0.50-0.05 =0.60

6)

probability that a vacationer will visit at least one of these magnificent attractions =0.75+0.30-0.25=0.80

7)

number of different arrangements =6*2*4=48

8)

a) number of permutations =⁵²P₅ =311875200

b) number of combinations =⁵²C₅ =2598960