11-1B (Participation)

What is the value of 8!

• 40320

• 36

• 362880

• 5040

Answer explanation

Use a calculator

A lock has four dials. On each dial are the digits 0 to 9. How many possible "combinations" are there?

• 40
• 5040
• 6561
• 10,000

Answer explanation

This is a FCP problem because you can repeat

10 - first dial

10 - second dial

1 0 - third dial

10 - fourth dial

Tomorrow you will learn that the term "combination" is not correct.

How many ways can you choose a manager and assistant from a 9-person task force?

Answer explanation

Solve using FCP

9*8

or

Solve using nPr

₉P₂ or nPr(9,2)

How many three-digit counting numbers are there?

• 990

• 900

• 999

• 1000

Answer explanation

This is a FCP problem because it allows repeats

9 - 1st digit (can't be 0)

10 - 2nd digit

10 - 3rd digit

A briefcase has a five-digit combination lock. The second digit in the combination is 5. At most how many different combinations must we try if we want to open the lock?

• 1000

• 10000

• 100000

• 99999

Answer explanation

This is a FCP problem because numbers CAN be repeated

10 - 1st digit

1 - 2nd digit (5)

10 - 3rd digit

10 - 4th digit

10 - 5th digit

Ivan has 4 different math books, 2 different biology books and 3 different physics books. In how many different ways can Ivan arrange his books in three different file holders, if each holder is for a different subject?

• 4.2.3

• 4!.2!.3!

• 4!.2!.3!.3!

• 4 + 2 + 3

Answer explanation

4! - math books

2! - biology books

3! - physics books

3! - which bin for which books

Answer explanation

Use calculator

It is an arrangement of objects in definite order.

• Combination

• Factorial

• Permutation

• Combinatorics

What is 5! + 4! ?

• 9

• 9!

• 144

• 120

Answer explanation

5! = 120

4! = 24

What does the P stand for in _nP_r?

• Partners
• Positions
• Papers
• Permutations