of ways in which the hall can be illuminated is
These are 11 questions in a examination paper of mathematics. A candidate has to answer
6 questions of which the question under 1 is compulsory. The total number of selections of his
answering in questions is __
Answers
Answered by
0
Answer:
There are 5 question in parts & 7 question in parts 2
atleast 8 question have to we attempted & 3 from lach part.
There are 3 options
(1)3 from part 1 & % from part 2
no, of ways
=
5
C
3
×
7
C
5
=
3!(5−3)!
5!
×
5!(7−5)!
7!
=
2
5×4
×=
2
7×6
=5×2×7×3
=210 ways
(2)4 from part 1 & 4 from part 2
=
5
C
4
×
7
C
4
=
4!(5−4)!
5!
×=
4!(7−4)!
7!
=5×=
3×2×1
7×6×5
=5×7×5
=175 ways
(3)5 from part 1 & 3 from part 2
=
5
C
5
×
7
C
3
=
5! 0!
5!
×=
3!(7−3)!
7!
=1×=
3×2
7×6×5
=35 ways
Total number of ways =210+175+35
420 ways
Similar questions