# What is permutation or combination problems?

## What is permutation or combination problems?

permutations and combinations, the various ways in which objects from a set may be selected, generally without replacement, to form subsets. This selection of subsets is called a permutation when the order of selection is a factor, a combination when order is not a factor.

How many questions comes in permutation and combination in JEE?

Chapter-wise Weightage of Maths Class 12 in JEE Main

Chapters Total Questions Weightage
Sets 1 3.3%
Permutations & Combinations 1 3.3%
Probability 1 3.3%
Complex Numbers 1 3.3%

### How many questions asked from permutation and combination in JEE?

= 120. Hence, required number = 5 + 20 + 60 + 120 + 120 = 325….JEE Main Maths Permutations and Combinations Previous Year Questions With Solutions.

No. of points selected out of 4 collinear points No. of points selected out of the remaining 6 points No. of straight-lines formed
0 2 4C0 × 6C2 = 15
1 1 4C1 × 6C1 = 24
2 0 1

Where do we use permutation and combination?

Hence, Permutation is used for lists (order matters) and Combination for groups (order doesn’t matter). Famous joke for the difference is: A “combination lock” should really be called a “permutation lock”. The order you put in the numbers of lock matters.

## Which chapter has highest weightage in JEE mains?

The following are the most important chapters for JEE Main 2022:

• Organic Compounds Containing Oxygen.
• Equilibrium.
• Chemical Kinetics.
• Transition Elements (d and f block)
• s-block Elements.
• Chemical Bonding And Molecular Structure.
• Some Basic Principles Of Organic Chemistry.
• p-block Elements.

What is the formula of permutation and combination?

One could say that a permutation is an ordered combination. The number of permutations of n objects taken r at a time is determined by the following formula: P(n,r)=n! (n−r)!

### Where permutation and combination is used?

What is a permutation problem?

A permutation is a mathematical technique that determines the number of possible arrangements in a set when the order of the arrangements matters. Common mathematical problems involve choosing only several items from a set of items in a certain order.

## What is the difference between a combination and permutation?

When the order does not matter, it is a combination. When the order matters, it is a permutation. This article explains the definition and gives solved problems on permutations and combinations.

Does the Order of a permutation matter?

If the order does matter then we have a permutation. It can be rightly said that a permutation is an ordered combination. Let us understand the difference between permutation and combination with an example.

### How many permutations of 5 books can be arranged 120 ways?

The number of permutations of n objects is n! = n (n – 1) (n – 2) … 2 . 1 Here n = 5. So, the number of permutations is 5! = 5 * 4 * 3 * 2 * 1 = 120. Hence, 5 books can be arranged in 120 ways.

What is a permutation when repetition is allowed?

★ When repetition is allowed: P is a permutation or arrangement of r things from a set of n things when repetition is allowed. We define P as: Let us assume that there are r boxes and each of them can hold one thing.