Questions
- John is taller than Jack, but shorter than Jim. Jim is shorter than Jill, but taller than Jane. Who is the tallest person in the group?
- A boat can travel 30 miles per hour in still water. If it travels 60 miles downstream and back, how long will the round trip take if the current is traveling at 10 miles per hour?
- A farmer has 17 cows. 7 of them are black and the rest are white. How many cows are white?
- There are 8 birds on a wire. 3 fly away, then 2 more come back. How many birds are on the wire now?
- If a train leaves town A at 8:00 am and another train leaves town B at 9:00 am, both heading toward each other at 30 mph and 50 mph respectively, at what time will they meet?
- A worker can paint a house in 4 days, while another worker can do it in 6 days. How long will it take if they both work together?
- Sarah has 3 red balls, 4 blue balls and 2 green balls. How many ways can Sarah choose 2 different colored balls?
- If you have 6 red marbles, 5 blue marbles, and 8 green marbles, how many different ways can you choose 4 marbles?
- There are 12 kids in a class. 7 like ice cream and 5 like cake. How many kids like either ice cream or cake or both?
- If you have 15 books, and you want to arrange them on a shelf, in how many different ways can you do that?
Answers
- Jill is the tallest person in the group.
- 4 hours
- 10 cows
- 7 birds
- The two trains will meet at 11:00am
- 2 days
- Sarah can choose the two different colored balls in a total of 12 ways
- 126
- 12 kids
- 15! (15 factorial), for a total of 151413*...21 = 3,628,800 different ways