A student has to answer 10 questions, choosing at least 4 from each of the parts A and B . If there are 6 questions in part A and 7 in part B , then the number of ways can the student choose 10 questions is

Step-by-step solution

Given, Total number of questions in part A=6 Total number of questions in part B=7 Pattern to choose 10 questions from 13 questions is 4 from part A and 6 from part B or 5 from part A and 5 from part B or 6 from part A and 4 from part B . Total required number of ways aligned &= ( 6 4 7 6 )+ ( 6 5 7 5 )+ ( 6 6 7 4 ) &=(15 7)+(6 21)+(1 35) &=105+126+35=266 aligned