Question 1 - Case Based Questions (MCQ) - Chapter 13 Class 12 Probability

Last updated at July 1, 2022 by Teachoo

Question

A coach is training 3 players. He observes that the player A can hit a target 4 times in 5 shots, player B can hit 3 times in 4 shots and the player C can hit 2 times in 3 shots.

From this situation answer the following:

Question 1

Let the target is hit by A, B and C. Then, the probability that A, B and, C all will hit, is

(a) 4/5Β

(b) 3/5Β

(c) 2/5Β

(d) 1/5

Question 2

Referring to (i), what is the probability that B, C will hit and A will lose?

(a) 1/10Β

(b) 3/10Β

(c) 7/10Β

(d) 4/10

Question 3

With reference to the events mentioned in (i), what is the probability that βany two of A, B and C will hit?

(a) 1/30Β

(b) 11/30Β

(c) 17/30Β

(d) 13/30

Question 4

What is the probability that βnone of them will hit the targetβ?

(a) 1/30Β

(b) 1/60Β

(c) 1/15Β

(d) 2/15

Question 5

What is the probability that at least one of A, B or C will hit the target?

(a) 59/60Β

(b) 2/5Β

(c) 3/5Β

(d) 1/60

Solve all your doubts with Teachoo Black (new monthly pack available now!)

Question A coach is training 3 players. He observes that the player A can hit a target 4 times in 5 shots, player B can hit 3 times in 4 shots and the player C can hit 2 times in 3 shots. From this situation answer the following:P(A) = Probability of A hitting the target
= π/π
P(B) = Probability of B hitting the target
= π/π
P(C) = Probability of C hitting the target
= π/π
Question 1 Let the target is hit by A, B and C. Then, the probability that A, B and, C all will hit, is (a) 4/5 (b) 3/5 (c) 2/5 (d) 1/5P(all hit) = Probability A will hit
Γ Probability B will hit
Γ Probability C will hit
= 4/5 Γ 3/4 Γ 2/3
= π/π
So, the correct answer is (c)
Question 2 Referring to (i), what is the probability that B, C will hit and A will lose? (a) 1/10 (b) 3/10 (c) 7/10 (d) 4/10P(B and C will hit and A will lose) = Probability A will not hit
Γ Probability B will hit
Γ Probability C will hit
= (πβπ/π)"Γ" π/π Γ π/π
= 1/5 Γ 3/4 Γ 2/3
= π/ππ
So, the correct answer is (a)
Question 3 With reference to the events mentioned in (i), what is the probability that βany two of A, B and C will hit? (a) 1/30 (b) 11/30 (c) 17/30 (d) 13/30 P(any two will hit)
= P(A will not hit) Γ P(B will hit) Γ P(C will hit)
+ P(A will hit) Γ P(B will not hit) Γ P(C will hit)
+ P(A will hit) Γ P(B will hit) Γ P(C will not hit)
= (1β4/5)"Γ" 3/4 Γ 2/3
+ 4/5 "Γ" (1β3/4)Γ 2/3
+4/5 "Γ" 3/4 Γ (1β2/3)
= 1/5 "Γ" 3/4 Γ 2/3
+ 4/5 "Γ" 1/4 Γ 2/3
+4/5 "Γ" 3/4 Γ 1/3
= 1/10+2/15+1/5
= ππ/ππ
So, the correct answer is (d)
Question 4 What is the probability that βnone of them will hit the targetβ? (a) 1/30 (b) 1/60 (c) 1/15 (d) 2/15P(none will hit) = Probability A will not hit
Γ Probability B will not hit
Γ Probability C will not hit
= (πβπ/π) Γ (πβπ/π)Γ(πβπ/π)
= 1/5Γ1/4Γ1/3
= π/ππ
So, the correct answer is (b)
Question 5 What is the probability that at least one of A, B or C will hit the target? (a) 59/60 (b) 2/5 (c) 3/5 (d) 1/60P( at least one will hit)
= P(exactly one will hit)
+ P(exactly two will hit)
+ P(all will hit)
P(exactly one will hit)
P(exactly one will hit)
= P(A will hit)ΓP(B will not hit) Γ P(C will not hit)
+ P (A will not hit) Γ P (B will hit) Γ P (C will not hit)
+ P (A will not hit)Γ P (B will not hit) Γ P (C will hit)
= 4/5Γ(1β3/4)Γ(1β2/3)
+(1β4/5)Γ3/4Γ(1β2/3)
+(1β4/5)Γ(1β3/4)Γ2/3= 4/5 "Γ" 1/4 Γ 1/3
+ 1/5 "Γ" 3/4Γ 1/3
+1/5 "Γ" 1/4 Γ 2/3
= 1/15+1/20+1/30
= π/ππP(exactly two will hit)
This is calculated in Question 3
P(exactly two will hit) = ππ/ππ
P(all will hit)
This is calculated in Question 1
P(all will hit) = π/πNow,
P(at least one will hit)
= P(exactly one will hit) + P(exactly two will hit) + P(all will hit)
= 9/60+13/30+2/5
= ππ/ππ
So, the correct answer is (a)

Made by

Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.

Hi, it looks like you're using AdBlock :(

Displaying ads are our only source of revenue. To help Teachoo create more content, and view the ad-free version of Teachooo... please purchase Teachoo Black subscription.

Please login to view more pages. It's free :)

Teachoo gives you a better experience when you're logged in. Please login :)

Solve all your doubts with Teachoo Black!

Teachoo answers all your questions if you are a Black user!