Question Bank  Probability  Gaurav Sharma

Number of Questions  30
Topic  Probability
Answer Key Available  Yes (Last post)
Source  Genius Tutorial forum

Q1) A box contains 5 green, 4 yellow and 3 white marbles. Three marbles are drawn at random. What is the probability that they are not of the same color?

Q2) Two couples and a single person are to be seated on 5 chairs such that no couple is seated next to each other. What is the probability of the above??
a) 1/3
b) 1/2
c) 2/5
d) 1/4

Q3) Four cards are drawn from a standard deck of playing cards without replacing a card after it is drawn. If the first 3 cards are hearts, what is the probability that the next card drawn is not a heart?

Q4) A college is composed of 70% men and 30% women. It is known that 40% of the men and 60% of the women smoke. What is the probability that a student seen smoking is a man?

Q5) A student arrives to bus stop between 7.55 and 8.05 every morning. And the bus leaves bus stop between 8.00 and 8.10 what is the probability that the student catches the bus

Q6) If n is an integer from 1 to 96, what is the probability for n*(n+1)*(n+2) being divisible by 8?
a) 25%
b) 50%
c) 62.5%
d) 72.5%
e) 75%

Q7) Two cards are drawn from a pack of wellshuffled cards. Find the probability that one is a CLUB and other is an ACE.

Q8) If 4 digit numbers greater than 5000 are randomly formed from the digits 0,1,3,5 and 7. What is the probability of forming a number divisible by 5 when the repetition of digits is not allowed?

Q9) I have 6 coins of different denominations in my pocket. If i take them out of my pocket one after another, what is the probability of taking out the 6 coins in descending order of their denominations?

Q10) In a function if 20 speakers give their speech, what is the probability that aspeaker A will speak before speaker B?

Q11) one point inside a square of side 2 cm is taken randomly. whats the probability of it being away from all corners by atleast 1 cm?

Q12) On one side of a coin there is the number 0 and on the other side the number 1. What is the probability that the sum of three coin tosses will be 2?

Q13) p and q are chosen from the set {1,2,3,4,5,6,7,8,9,10} with replacement. What is the probability that the roots of x^2 + px + q = 0 are real ?

Q14) m and n are two positive integers lying from 1 to 100. What is the probability that 3^m + 7^n has the last digit 8 ?

Q15) What is the probability that a rectangle picked at random in a 6×6 grid is a square ?

Q16) If four numbers are multiplied together, then find the probability that the product is divisible by 5 or 10 is??
169/625,
369/625
169/1626
None Of These

Q17) Two numbers are selected at random from the integers 1 through 9.If the sum is even,find the probability that both numbers are odd?

Q18) All possible fourdigit numbers are formed by using the digits 3, 4, 5 and 6, without repetition of the digits. If a number chosen randomly out of the formed numbers, what is the probability that the chosen number is an even multiple of three?

Q19) If two squares are choosen from a chess board with 64 squares; what is the probability that they share a common side?