Probability MCQs
Showing 19 questions (Total: 119)
A die is rolled and a coin is tossed What is the probability that a 3 will be rolled and a tail tossed?
Correct Answer:
D: 1/12
Explanation:
A die is rolled and a coin is tossed What is the probability that a 3 will be rolled and a tail tossed? Correct Answer 1/12 এখানে,একটি নিরপেক্ষ ছক্কার ৩ এবং মুদ্রার Tail আসে ১ বার (3T) অতএব, অনুকূল ফলাফল = 1 এবং মোট ফলাফল = 12 অতএব, সম্ভব্যতা = 1/2
একটি মুদ্রা ২ বার নিঃক্ষেপ করলে অন্তত ১ বার Head পড়ার সম্ভবনা কত?
Correct Answer:
খ: ১/৪
Explanation:
একটি মুদ্রা ২ বার নিঃক্ষেপ করলে অন্তত ১ বার Head পড়ার সম্ভবনা কত? সঠিক উত্তর ১/৪ ১ম বার হেড পাওয়ার সম্ভাবনা = 1/2২য় ” ” ” ” = 1/2∴∴ উভয় ক্ষেত্রে হেড পাওয়ার সম্ভাবনা = 1/2×/1/2 = 1/4
একটি গোল মুদ্রা টেবিলে রাখা হল । এই মুদ্রার চারপাশে একই মুদ্রা কতটি রাখা যেতে পারে যেন তারা মাঝের মুদ্রাটিকে ও দু'প্রাশের দুটি মুদ্রাকে স্পর্শ করে ?
Correct Answer:
খ: ৬
Explanation:
একটি গোল মুদ্রা টেবিলে রাখা হল । এই মুদ্রার চারপাশে একই মুদ্রা কতটি রাখা যেতে পারে যেন তারা মাঝের মুদ্রাটিকে ও দু'প্রাশের দুটি মুদ্রাকে স্পর্শ করে ? সঠিক উত্তর ৬ ধরি, A হচ্ছে কেন্দ্রে রাখা মুদ্রা এবং B হচ্ছে চারপাশে রাখা মুদ্রাগুলোর একটি। আবার, মুদ্রাগুলোর ব্যাসার্ধ্য = a A কেন্দ্রবিশিষ্ট বৃত্তের কেন্দ্র A কে কেন্দ্র করে B কেন্দ্র বিশিষ্ট বৃত্তের উপর দুইটি স্পর্শক টানি। স্পর্শকদ্বয় B কেন্দ্রবিশিষ্ট বৃত্তের C ও D বিন্দুতে স্পর্শ করে। যেখানে, BCলম্বAC এবং BDলম্বAD. সুতরাং এখন, AB = a + a = 2a; BC = a ACB সমকোণী ত্রিভুজে, Sin BAC = BC/AB = a/2a = 1/2 = Sin 30° এখানে, একইভাবে, তাহলে, কেন্দ্রে 60° কোণ উৎপন্ন করে ১ টি চারপাশের মুদ্রা কেন্দ্র 360° কোণ উৎপন্ন করে = (360/60) টি মুদ্রা = 6 টি নির্ণেয় মুদ্রার সংখ্যা ৬ টি।
A coin is thrown 3 times in the air. What is the probability that one head is followed by two tails?
Correct Answer:
C: 18
Explanation:
A coin is thrown 3 times in the air. What is the probability that one head is followed by two tails? Correct Answer 18 The occurrence of 1H & 2T are: HTT, THT, TTH, so, n(A) = 3 Total favourable cases while a coin tossed thrice is n (S) = 23 = 8 Therefore probability of getting 2H & 1T is P(A) = 3/8.
Jennifer flipped a coin three times and got heads each time. What is the probability that she gets heads on the next flip?
Correct Answer:
C: 1/2
আবহাওয়া অফিসের রিপোর্ট অনুযায়ী ২০২২ সালে মে মাসে চতুর্থ সপ্তাহে বৃষ্টি হয়েছে মোট ৫ দিন। ঐ সপ্তাহে রবিবারে বৃষ্টি না হওয়ার সম্ভাবনা কত?
Correct Answer:
ক: ২/৭
Explanation:
আবহাওয়া অফিসের রিপোর্ট অনুযায়ী ২০২২ সালে মে মাসে চতুর্থ সপ্তাহে বৃষ্টি হয়েছে মোট ৫ দিন। ঐ সপ্তাহে রবিবারে বৃষ্টি না হওয়ার সম্ভাবনা কত? সঠিক উত্তর ২/৭ ১ সপ্তাহ = ৭ দিনবৃষ্টি হয়েছে = ৫ দিনবৃষ্টি হওয়ার সম্ভাবনা = ৫/৭রবিবারে বৃষ্টি না হওয়ার সম্ভাবনা =১ - ৫/৭ = ২/৭ (উত্তর)
A hat contains 12 cards marked with a star and 18 unmarked cards. What is the probability that one card slelected at random will be marked with a star?
Correct Answer:
B: 2/5
A certain jar contain 60 jellybeans where 22 white, 18 green, 11 yellow, 5 red and 4 purple . If a jellybean is to be chosen at random , what is the probability that the jellybean will be neither red not purple?
Correct Answer:
B: 0.85
In a group of buffaloes and ducks, the number of legs is 24 more than twice the number of heads. What is the number of buffaloes?
Correct Answer:
A: 12
Explanation:
In a group of buffaloes and ducks, the number of legs is 24 more than twice the number of heads. What is the number of buffaloes? Correct Answer 12 Let the number of buffaloes be x and the number of ducks be y. Each buffalo has 1 head & 4 legs.Each duck has 1 head & 2 legs.So the number of heads =x+y and the number of legs=4x+2y.So, by the given condition,4x+2y=2(x+y)+24⇒4x−2x+2y−2y=24⇒2x=24⇒x=12
A fair coin is thrown in the air four times. If the coin lands with the head up on the first three tosses, what is the probability that the coin will land with the head up on the fourth toss ?
Correct Answer:
B: 1/2
Explanation:
A fair coin is thrown in the air four times. If the coin lands with the head up on the first three tosses, what is the probability that the coin will land with the head up on the fourth toss ? Correct Answer 1/2 The results are independent. P(head on 4th toss) = 1/2
A number is selected at random from 40 to 59 inclusive . What is the probability that the number is prime number ?
Correct Answer:
A: 3/11
Explanation:
A number is selected at random from 40 to 59 inclusive . What is the probability that the number is prime number ? Correct Answer 3/11 Total number of numbers = 59 - 40 + 1 = 20 Prime numbers : 41, 43, 47, 53, 59 = 5 in total So, the probability = 5/20 = 1/4
A special lottery is to be held to select the student who will live in the only deluxe room in a dormitory. There are 100 seniors, 150 juniors, and 200 sophomores who applied. Each senior's name is placed in the lottery 3 times, each junior's name, 2 times, and each sophomore's, 1 time. What is the probability that a senior's name will be chosen?
Correct Answer:
D: 3/8
Explanation:
A special lottery is to be held to select the student who will live in the only deluxe room in a dormitory. There are 100 seniors, 150 juniors, and 200 sophomores who applied. Each senior's name is placed in the lottery 3 times, each junior's name, 2 times, and each sophomore's, 1 time. What is the probability that a senior's name will be chosen? Correct Answer 3/8 Total number of seniors' names = 3 x 100 = 300 Total number of juniors' names = 2 x 150 = 300 Total number of sophomores' names = 200 Total student names for lottery = 300 + 300 + 200 = 800 Probability of a senior's name to be chosen = 300 / 800 = 3/8
Certain number of children were playing a game of football. There was a trial taking place on the field. In this trial the probability that a goal is scored is 2/5. The probability that a girl hits a goal is 7/10 whereas the probability that a boy hits a goal is 1/5. What will be the probability that not only a goal is hit but it is also hit by a boy?
Correct Answer:
D: 2/25
Explanation:
Certain number of children were playing a game of football. There was a trial taking place on the field. In this trial the probability that a goal is scored is 2/5. The probability that a girl hits a goal is 7/10 whereas the probability that a boy hits a goal is 1/5. What will be the probability that not only a goal is hit but it is also hit by a boy? Correct Answer 2/25 দেয়া আছে, একজন girl - এর goal করার সম্ভাব্যতা = 710 boy " " " " = 15 যেকোনো একজন দ্বারা " " " " = 25 ∴ আমরা জানি, দুটি event একসাথে ঘটার সম্ভাব্যতা হচ্ছে তাদের গুণফলের সমান। ∴ goal একজন ছেলে করবে এমন সম্ভব্যতা = 25×15 = 225
Certain numbers of children were playing a game of football. There was a trial taking place on the field. In this trial the probability that a goal is scored is 2/5. The probability that a gril hits a goal is 7/10 whereas the probability than a boy hits a goal is 1/5. What will be the probability that not only a goal is hit but it is also hit by a boy?
Correct Answer:
D: 2/25
Explanation:
Certain numbers of children were playing a game of football. There was a trial taking place on the field. In this trial the probability that a goal is scored is 2/5. The probability that a gril hits a goal is 7/10 whereas the probability than a boy hits a goal is 1/5. What will be the probability that not only a goal is hit but it is also hit by a boy? Correct Answer 2/25 We know that, the probability that two events will take place simultaneously is denoted by the product of the individual occurences of each of the different events. So The probability that a goal is scored and it is also scored by a boy = 25×15 = 225
Four subjects ---physics, Chemistry, Mathematics and Biology ---were taught in four consecutive periods of one hour each starting from 8.00 a.m. At what time was the chemistry period scheduled? 1. Mathematics period ended at 10.00 a.m, which was preceded by Biology. 2. Physics was scheduled in the last period. 3. Mathematics period was immediately followed by Chemistry.
Correct Answer:
D: Only 1 and either 2 or 3
Explanation:
Four subjects ---physics, Chemistry, Mathematics and Biology ---were taught in four consecutive periods of one hour each starting from 8.00 a.m. At what time was the chemistry period scheduled? 1. Mathematics period ended at 10.00 a.m, which was preceded by Biology. 2. Physics was scheduled in the last period. 3. Mathematics period was immediately followed by Chemistry. Correct Answer Only 1 and either 2 or 3 ইঙ্গিতগুলো নিচে ক্লাস রুটিন আকারে সাজালেই বোঝা যাবে Chemistry ক্লাস কখন হবে।
All possible three digit numbers are formed formes by 1, 2, 3 . If one number is chosen randomly, the probability that it would be divisible by 111 is____
Correct Answer:
Correct Answer:
When they had a meeting seven company executives __ T, U, V, W, X, Y and Z ___ sit at a rectangular table .Three executives sit along one side of the table , and three sit along the other side, each directly opposite one of the other three. The seventh sits at the head of the table . There is no seat at the foot of the table . Ualways sits in one of te two seats farthest from the head of the table. Y and V always sit next to each other .V never sits next to Z . If Z does not sit at the head of the table, W sits there. If W sits directly opposite T, X must sit next to which of the following excutives?
Correct Answer:
A: T
Explanation:
When they had a meeting seven company executives __ T, U, V, W, X, Y and Z ___ sit at a rectangular table .Three executives sit along one side of the table , and three sit along the other side, each directly opposite one of the other three. The seventh sits at the head of the table . There is no seat at the foot of the table . Ualways sits in one of te two seats farthest from the head of the table. Y and V always sit next to each other .V never sits next to Z . If Z does not sit at the head of the table, W sits there. If W sits directly opposite T, X must sit next to which of the following excutives? Correct Answer T square এর ক্ষেত্রফল = z2 ∴half circle = 12πz22 = πz28
In a zoo, there are Rabbits and Pigeons. It heads are counted s, there are 200 and if legs are counted there are 580. How many pigeons are there ?
Correct Answer:
C: 110
Explanation:
In a zoo, there are Rabbits and Pigeons. It heads are counted s, there are 200 and if legs are counted there are 580. How many pigeons are there ? Correct Answer 110 Heads Count = 200 Legs count = 580 Average Legs count for per head = 580/200 = 29/10 Rabbits : Pigeons = 9/10: 11/10 = 9 : 11 Number of Pigeons = 200 × 11/20 = 110
A bag contains 2 red, 3 green and 2 blue balls .Two balls are drawn at random. What is the probability that none of the balls drawn is blue?
Correct Answer:
C: 10/21
Explanation:
A bag contains 2 red, 3 green and 2 blue balls .Two balls are drawn at random. What is the probability that none of the balls drawn is blue? Correct Answer 10/21 Total number of balls = (2 + 3 + 2) = 7 Let S be the sample space Then, n(S) = Number of ways of drawing 2 balls out of 7 n(S) = 7C2 n(S) = (7 × 6)/(2 × 1) n(S) = 21 Let E = Event of 2 balls, none of which is blue ∴ n(E) = Number of ways of drawing 2 balls out of (2 + 3) balls n(E) = 5C2 n(E) = (5 × 4)/(2 × 1) n(E) = 10 ∴P(E) = n(E)/n(S) = 10/21