Combinatorics
Math ⇒ Statistics and Probability
Combinatorics starts at 9 and continues till grade 12.
QuestionsToday has an evolving set of questions to continuously challenge students so that their knowledge grows in Combinatorics.
How you perform is determined by your score and the time you take.
When you play a quiz, your answers are evaluated in concept instead of actual words and definitions used.
See sample questions for grade 9
How many 3-digit numbers can be formed using the digits 1, 2, 3, 4, 5 if no digit is repeated?
How many different ways can you arrange the letters in the word 'MATH'?
How many ways can 3 students stand in a line?
How many ways can 4 people be seated in a row of 4 chairs?
How many 3-digit numbers can be formed using the digits 1, 2, 3, 4, 5 if no digit is repeated?
How many ways can 4 people be seated in a row of 4 chairs?
How many ways can you arrange the letters in the word 'BANANA'?
How many ways can you arrange the letters in the word 'LEVEL'?
The number of ways to choose 2 students from a group of 5 is: (1) 10 (2) 20 (3) 5 (4) 15
Which formula is used to calculate the number of combinations of n objects taken r at a time? (1) n!/(n-r)! (2) n!/(r!(n-r)!) (3) n^r (4) n+r-1Cr
Which of the following is a combination? (1) Arranging books on a shelf (2) Selecting team members (3) Assigning seats (4) Organizing a race
Which of the following is a permutation problem? (1) Choosing 3 books from a shelf (2) Arranging 3 books on a shelf (3) Selecting 3 students for a team (4) Picking 3 cards from a deck
Fill in the blank: The number of ways to arrange 4 different books on a shelf is _______.
Fill in the blank: The number of ways to arrange n objects in a circle is _______.
Fill in the blank: The number of ways to arrange n objects in a row is _______.
Fill in the blank: The number of ways to arrange n objects taken r at a time is _______.
True or False: 0! (zero factorial) is equal to 1.
True or False: In combinations, the order of selection does not matter.
True or False: The number of permutations of n objects taken r at a time is given by n!/(n-r)!
True or False: The number of ways to arrange 3 objects in a row is 6.
