Class 11 Mathematics - Permutations And Combinations - Derivations of formulas and their connections Expert Quiz

Mathematics Permutations And Combinations Derivations of formulas and their connections Expert Class 11 Level 60

Level 60 • 2/50 questions • 25 seconds per question.

Level readiness 2/50 Questions
Time Left 00:50 25 sec/question
RewardsCoins + XP
ModeClassic Quiz
Previous Next Level
Share
This level needs 48 more active questions. Admin panel me same class, subject, difficulty aur level_no 60 par question add karein.
Question 1 / 2 0 score
Answered 0/2 Correct 0 Time 00:50
Question 1/2 Expert Mathematics Permutations and Combinations Permutations Class 11 Level 60

(6) अलग-अलग पत्रों को (6) अलग-अलग लिफाफों में रखा जाए। ठीक (4) पत्र सही लिफाफे में जाएं, ऐसी व्यवस्थाओं की संख्या कितनी है?

(6) distinct letters are placed into (6) distinct envelopes. How many arrangements have exactly (4) letters in their correct envelopes?

Explanation opens after your attempt
Correct Answer

C. (15)

Step 1

Concept

Choose the (4) correct letters in \(\binom{6}{4}\) ways, and derange the remaining (2) letters in (!2=1) way. Exam tip: split exact conditions into fixed and deranged parts.

Step 2

Why this answer is correct

The correct answer is C. (15). Choose the (4) correct letters in \(\binom{6}{4}\) ways, and derange the remaining (2) letters in (!2=1) way. Exam tip: split exact conditions into fixed and deranged parts.

Step 3

Exam Tip

सही जाने वाले (4) पत्र \(\binom{6}{4}\) तरीकों से चुनें और बाकी (2) का derangement (!2=1) है। परीक्षा में ठीक वाली शर्त के लिए fixed और deranged भाग अलग करें।

Open Question Page
Ask Friends
Question 2/2 Expert Mathematics Permutations and Combinations Permutations Class 11 Level 60

(7) अलग-अलग पुरस्कार (7) छात्रों में बांटने हैं। ठीक (2) विशेष पुरस्कार अपने निर्धारित छात्रों को मिलें, तो कितने तरीके होंगे?

(7) distinct prizes are assigned to (7) students. How many assignments have exactly (2) prizes going to their designated students?

Explanation opens after your attempt
Correct Answer

B. (1854)

Step 1

Concept

Choose the (2) correctly assigned prizes in \(\binom{7}{2}\) ways and derange the remaining (5), giving (!5=44). Exam tip: use derangement for exactly correct cases.

Step 2

Why this answer is correct

The correct answer is B. (1854). Choose the (2) correctly assigned prizes in \(\binom{7}{2}\) ways and derange the remaining (5), giving (!5=44). Exam tip: use derangement for exactly correct cases.

Step 3

Exam Tip

सही जाने वाले (2) पुरस्कार \(\binom{7}{2}\) तरीकों से चुनें और बाकी (5) का derangement (!5=44) है। परीक्षा में exactly correct cases के लिए derangement का प्रयोग करें।

Open Question Page
Ask Friends

Mathematics Quiz Navigation

Mathematics Subject

All difficulty level maps

Derivations of formulas and their connections Topic

Topic question list

Permutations And Combinations Chapter

Chapter question list

Search Mathematics

Find related MCQs

All Subjects

Choose another subject
FAQs

Class 11 Mathematics Quiz FAQs

How many questions are in this quiz?

This level is designed for 50 active questions. Currently 2 questions are available for the selected class and difficulty.

Is there a timer in this quiz?

Yes, the timer uses 25 seconds per question for Expert difficulty and shows the total remaining time on the page.

Can I open each question separately?

Yes, every question has its own SEO-friendly page with answer, explanation and related practice links.