A question paper has 2 parts, A & B, each containing 6 questions. If a student has to choose 4 from part A &3 from part B, in how many ways can he choose the questions?  Choose the correct answer.
A) 100
B) 200
C) 350
D) 150
E) 140
There 6 questions in part A out of which 4 question can be chosen as = 6C4.   Similarly, 3 questions can be chosen from 6 questions of Part B as = 6C3.   Hence, total number of ways,   =6C4*6C3   =[6!/(2!4!)]*[6!/(3!*3!)]   = {15}*{6*5*4*3/(3*2*1)}   = 300.   150
<result>D</result>
A question paper has 2 parts, A & B, each containing 6 questions. If a student has to choose 4 from part A &3 from part B, in how many ways can he choose the questions?