Search for: If 15Cr+1:15C3r=3:11 then value of r is If 15Cr+1:15C3r=3:11 then value of r is A2B3C4D5 Fill Out the Form for Expert Academic Guidance!l Grade ---Class 1Class 2Class 3Class 4Class 5Class 6Class 7Class 8Class 9Class 10Class 11Class 12 Target Exam JEENEETCBSE +91 Preferred time slot for the call ---9 am10 am11 am12 pm1 pm2 pm3 pm4 pm5 pm6 pm7 pm8pm9 pm10pm Please indicate your interest Live ClassesBooksTest SeriesSelf Learning Language ---EnglishHindiMarathiTamilTeluguMalayalam Are you a Sri Chaitanya student? NoYes Verify OTP Code (required) I agree to the terms and conditions and privacy policy. Solution:Note that 0≤3r≤15⇒0≤r≤5. Also, 15!(14−r)!(r+1)!×(3r)!(15−3r)!15!=311⇒ (3r)!(15−3r)!(14−r)!(r+1)!=311 1For the denominator, to be divisible by 11,11∣(14−r)!Setting 14−r=11. ⇒ r=3Putting r = 3, in LHS of (1) we getLHS of (1) 9!6!11!4!=6×511×10=311= = RHS of (1) ∴ r=3 Related content Top 5 Reasons To Study Science After 10th Application for Teaching Job Railway Jobs After 10th CBSE Class 12 Computer Science Answer Key and Paper Analysis 2024 – Student Feedback and Expert View Fractions Class 6 Worksheet Genetics and Evolution | Mind Map Kerala NEET UG Merit List 2023 NEET Exam Centres in Hyderabad 2024 Ecology & Environments NEET Exam Centres in Maharashtra 2024