JEE Main 2022 · MathsNumerical answerNumerical valueMediumMulti-step

JEE Main 29 June 2022, Shift 1, Maths Q30

Question 30 of 90 in this shift, Maths question 30 of 30, Section B.

Let

b_1b_2b_3b_4

be a 4-element permutation with

b_i \in \{1, 2, 3, \ldots\ldots, 100\}

for

1 \le i \le 4

and

b_i \ne b_j

for

i \ne j

, such that either

b_1, b_2, b_3

are consecutive integers or

b_2, b_3, b_4

are consecutive integers. Then the number of such permutations

b_1b_2b_3b_4

is equal to ____________.

Official answer

18915

NTA final key (2022 Session 1).

Chapter: Permutations and Combinations
Topic: Permutations and Combinations
Idea tested: Permutations of Distinct Objects

Same idea in other shifts

Asked 10× in all

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25 Jun 2022, Shift 2 · Q27The total number of three-digit numbers, with one digit repeated exactly two times, is ____________.MediumNumerical value
30 Jun 2022, Shift 1 · Q21The number of 6-digit numbers made by using the digits 1, 2, 3, 4, 5, 6, 7, without repetition and which are multiple of 15 is __________.MediumNumerical value
26 Aug 2021, Shift 1 · Q81The number of three-digit even numbers, formed by the digits 0, 1, 3, 4, 6, 7 if the repetition of digits is not allowed, is __________.EasyNumerical value
25 Feb 2021, Shift 1 · Q84The total number of numbers, lying between 100 and 1000 that can be formed with the digits 1, 2, 3, 4, 5, if the repetition of digits is…MediumNumerical value
25 Jul 2021, Shift 2 · Q63If ${}^nP_r={}^nP_{r+1}$ and ${}^nC_r={}^nC_{r-1}$ , then the value of r is equal to :EasySingle correct
9 Jan 2020, Shift 1 · Q56If the number of five digit numbers with distinct digits and 2 at the $10^{\mathrm{th}}$ place is 336 k, then k is equal to :MediumSingle correct

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.