Scroll:Probability >> probability >> saq (4491)


Written Instructions:

For each Multiple Choice Question (MCQ), four options are given. One of them is the correct answer. Make your choice (1,2,3 or 4). Write your answers in the brackets provided..

For each Short Answer Question(SAQ) and Long Answer Question(LAQ), write your answers in the blanks provided.

Leave your answers in the simplest form or correct to two decimal places.



 

1)  

 A two digit number is formed with the digits 3, 6 and 8. Find the probability that the number so formed is greater than 68 (repetition of digits is not allowed).


Answer:_______________




2)  

 A number is selected at random from integers 1 to 100. Find the probability that it is a perfect square


Answer:_______________




3)  

Two dice are rolled and the product of the outcomes (numbers) are found. What is the probability that the product so found is a prime number


Answer:_______________




4)  

 A two digit number is formed with the digits 3, 4 and 8. Find the probability that the number so formed is greater than 48 (repetition of digits is not allowed).


Answer:_______________




5)  

 A number is selected at random from integers 1 to 100. Find the probability that it is not a perfect cube.


Answer:_______________




6)  

 20 cards are numbered from 1 to 20 . One card is grawn at randon, What is the probablity that the number on the card is a multiples of 4


Answer:_______________




7)  

 There dice are thrown simultaneously. Find the probability of getting the same number on all the three dice.


Answer:_______________




8)  

For a sightseeing trip, a tourist selects a country randomly from Argentina, Bangladesh, China, Angola, Russia and Algeria. What is the probability that the name of the selected country will begin with A


Answer:_______________




9)  

 20 cards are numbered from 1 to 20 . One card is grawn at randon, What is the probablity that the number on the card is not a multiples of 6


Answer:_______________




10)  

 A two digit number is formed with the digits 3, 4 and 9. Find the probability that the number so formed is greater than 49 (repetition of digits is not allowed).


Answer:_______________




 

1)  

 A two digit number is formed with the digits 3, 6 and 8. Find the probability that the number so formed is greater than 68 (repetition of digits is not allowed).

Answer: 13


SOLUTION 1 :

Sample space, S =  { 36, 38, 63, 68, 83, 86 }

n(S) = 6.

Let A be the event of the number so formed is greater than 68.

A = { 83, 86 }.

n(A) = 2.

P(A) = n(A)n(S)

       =   26  =   13

 



2)  

 A number is selected at random from integers 1 to 100. Find the probability that it is a perfect square

Answer: 110


SOLUTION 1 :

Sample space, S = { 1,2,3,  ...... 100 }

n(S) = 100.

Let A be the event of choosing a perfect square number

A = { 1, 4, 9, 16, 25, 36, 49, 64, 81, 100 }

n(A) = 10.

P(A) = n(A)n(S)

       =   10100  =   110



3)  

Two dice are rolled and the product of the outcomes (numbers) are found. What is the probability that the product so found is a prime number

Answer: 16


SOLUTION 1 :

When two dice are thrown, the sample space is 

S = { (1,1), (1,2), (1,3), (1,4), (1,5), (1,6),

        (2,1), (2,2), (2,3), (2,4), (2,5), (2,6),

        (3,1), (3,2), (3,3), (3,4), (3,5), (3,6),

        (4,1), (4,2), (4,3), (4,4), (4,5), (4,6),

        (5,1), (5,2), (5,3), (5,4), (5,5), (5,6),

        (6,1), (6,2), (6,3), (6,4), (6,5), (6,6) }

n (S) = 6 x 6 = 36.

Let A be the event of getting two digit number formed is a prime number.

A =  { (1,2), (1,3), (1,5), (2,1), (3,1), (5,1) }

n(A) = 6.

Hence P(A) = n(A)n(S)

                 = 636  = 16 .

 

 



4)  

 A two digit number is formed with the digits 3, 4 and 8. Find the probability that the number so formed is greater than 48 (repetition of digits is not allowed).

Answer: 13


SOLUTION 1 :

Sample space, S =  { 34, 38, 43, 48, 83, 84 }

n(S) = 6.

Let A be the event of the number so formed is greater than 48.

A = { 83, 84 }.

n(A) = 2.

P(A) = n(A)n(S)

       =   26  =   13

 



5)  

 A number is selected at random from integers 1 to 100. Find the probability that it is not a perfect cube.

Answer: 2425


SOLUTION 1 :

Sample space, S = { 1,2,3,  ...... 100 }

n(S) = 100.

Let B be the event of choosing a number, which is not a perect cube.

Perfect cube numbers from 1 to 100 is C = { 1, 8, 27, 64}.

n(C) = 4.

n(B) = n(S) - n(C)

n(B) = 100 - 4 = 96.

n(B) = 96.

P(A) = n(B)n(S)

       =   96100  =   2425



6)  

 20 cards are numbered from 1 to 20 . One card is grawn at randon, What is the probablity that the number on the card is a multiples of 4

Answer: 14


SOLUTION 1 :

Sample space , n(S) = 20.

Let A be the event of drawing a card, which is multiple of 4.

A = { 4, 8, 12, 16, 20 }

n(A) = 5

P(A) = n(A)n(S)

        = 520  =   14

 



7)  

 There dice are thrown simultaneously. Find the probability of getting the same number on all the three dice.

Answer: 136


SOLUTION 1 :

When three dice are rolled, the sample space

S = { (1,1,1), (1,1,2), (1,1,3), ... (6,6,6).

S contains 6 x 6 x 6 = 216 outcomes. 

Let A be the event of getting the sum of face numbers are same.

A = { (1,1,1), (2,2,2), (3,3,3), (4,4,4), (5,5,5), (6,6,6) }

n(A) = 6.

P(A) = n(A)n(S)

        = 6216  = 136



8)  

For a sightseeing trip, a tourist selects a country randomly from Argentina, Bangladesh, China, Angola, Russia and Algeria. What is the probability that the name of the selected country will begin with A

Answer: 12


SOLUTION 1 :

Sample space, S = { Argentina, Bangaladesh, China, Angola, Russia, Algeria }

n(S) = 6.

Let C be the event of selecting the country will begin with A.

C = { Argentina, Angola, Algeria }.

n(C) = 3.

P(C) = n(C)n(S)

        = 36  =   12



9)  

 20 cards are numbered from 1 to 20 . One card is grawn at randon, What is the probablity that the number on the card is not a multiples of 6

Answer: 1720


SOLUTION 1 :

Sample space , n(S) = 20.

Let A be the event of drawing a card, which is not a multiple of 6.

B = { 1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 19, 20 }.

n(B) = 17

P(A) = n(B)n(S)

        = 1720



10)  

 A two digit number is formed with the digits 3, 4 and 9. Find the probability that the number so formed is greater than 49 (repetition of digits is not allowed).

Answer: 13


SOLUTION 1 :

Sample space, S =  { 34, 39, 43, 49, 93, 94 }

n(S) = 6.

Let A be the event of the number so formed is greater than 49.

A = { 93, 94 }.

n(A) = 2.

P(A) = n(A)n(S)

       =   26  =   13