Advertisements
Advertisements
प्रश्न
A question paper has two sections. section I has 5 questions and section II has 6 questions. A student must answer at least two question from each section among 6 questions he answers. How many different choices does the student have in choosing questions?
Advertisements
उत्तर
There are 11 questions, out of which 5 questions are from section I and 6 questions are from section II.
The student has to select 6 questions taking at least 2 questions from each section.
Consider the following table:
| Case I | Case II | Case III | |
| No. of questions | Sec I (2Q) Sec II (4Q) |
Sec I (3Q) Sec II (3Q) |
Sec I (4Q) Sec II (2Q) |
| Number of ways | 5C2 × 6C4 = 10 × 15 = 150 |
5C3 × 6C3 = 10 × 20 = 200 |
5C4 × 6C2 = 5 × 15 = 75 |
∴ Number of choices = 150 + 200 + 75 = 425
∴ In 425 ways students can select 6 questions, taking at least 2 questions from each section.
APPEARS IN
संबंधित प्रश्न
Find the value of 15C4
Find the value of `""^15"C"_4 + ""^15"C"_5`
If `""^"n""P"_"r" = 1814400` and `""^"n""C"_"r"` = 45, find r.
If 20 points are marked on a circle, how many chords can be drawn?
Find the number of diagonals of an n-shaded polygon. In particular, find the number of diagonals when: n = 10
Find the number of diagonals of an n-shaded polygon. In particular, find the number of diagonals when: n = 15
Ten points are plotted on a plane. Find the number of straight lines obtained by joining these points if four points are collinear.
Find the number of triangles formed by joining 12 points if four points are collinear.
Find n if `""^"n""C"_8 = ""^"n""C"_12`
Find n, if `""^21"C"_(6"n") = ""^21"C"_(("n"^2 + 5)`
Find n, if `""^(2"n")"C"_("r" - 1) = ""^(2"n")"C"_("r" + 1)`
Find x if `""^"n""P"_"r" = "x" ""^"n""C"_"r"`
Find the differences between the largest values in the following: `""^15"C"_r "and" ""^11"C"_r`
A question paper has two sections. section I has 5 questions and section II has 6 questions. A student must answer at least two questions from each section among 6 questions he answers. How many different choices does the student have in choosing questions?
Five students are selected from 11. How many ways can these students be selected if two specified students are selected?
Nine friends decide to go for a picnic in two groups. One group decides to go by car and the other group decides to go by train. Find the number of different ways of doing so if there must be at least 3 friends in each group.
Find r if 14C2r : 10C2r–4 = 143 : 10
Find the number of ways of drawing 9 balls from a bag that has 6 red balls, 8 green balls, and 7 blue balls so that 3 balls of every colour are drawn
After a meeting, every participant shakes hands with every other participants. If the number of handshakes is 66, find the number of participants in the meeting.
If 20 points are marked on a circle, how many chords can be drawn?
Find the number of diagonals of an n-sided polygon. In particular, find the number of diagonals when n = 15
Find the number of diagonals of an n-sided polygon. In particular, find the number of diagonals when n = 8
Ten points are plotted on a plane. Find the number of straight lines obtained by joining these points if no three points are collinear
Find the number of triangles formed by joining 12 points if four points are collinear
A word has 8 consonants and 3 vowels. How many distinct words can be formed if 4 consonants and 2 vowels are chosen?
Find n if 23C3n = 23C2n+3
Find n if 21C6n = `""^21"C"_(("n"^2 + 5))`
Find n if nCn–2 = 15
Find the value of `sum_("r" = 1)^4 ""^((21 - "r"))"C"_4`
Five students are selected from 11. How many ways can these students be selected if two specified students are not selected?
Answer the following:
Ten students are to be selected for a project from a class of 30 students. There are 4 students who want to be together either in the project or not in the project. Find the number of possible selections
Answer the following:
There are 4 doctors and 8 lawyers in a panel. Find the number of ways for selecting a team of 6 if at least one doctor must be in the team
If 'n' is positive integer and three consecutive coefficient in the expansion of (1 + x)n are in the ratio 6 : 33 : 110, then n is equal to ______.
What is the probability of getting a “FULL HOUSE” in five cards drawn in a poker game from a standard pack of 52-cards?
[A FULL HOUSE consists of 3 cards of the same kind (eg, 3 Kings) and 2 cards of another kind (eg, 2 Aces)]
