Why should P(A ^ B) be 0?? That would imply, that there is no possibility of both of them being born on Monday!! Is that the case??
Actually, the births of 2 people are independent events (Hoping that they are not twins ) So probability if anyone being born on Monday is P(A) = P(B) = 1/7 Since the Events are independent, laws of probability state that P (A ^ B) = P(A)*P(B) = 1/7 * 1/7 = 1/49
Hope this clears ur doubt
hey jawaharnr,
The answer is right and i also solved it exactly the same way but i am not completely convinced with the answer explaination...
it says 1/7(prob of person A to born on monday) + 1/7(prob of person B to born on Monday) - 1/49(P (A nd B)) = 13/49.
I saw two similar questions have different explanation and two different answers.
Q1. How many ways 5 boys and 6 girlsbe arranged in a row so that no two boys are together. Below are the answer choices: a. 7 * 6! b. 6!*5!*2 c. 6!*5! P 5
d. 7 * 5! P 5 e.6 * 6! P 5 Answer is a.
Q2. How many ways can 6 positive and 5 negative sings be arranged in a row so that no two negative sings are together. Below are the answer choices:
a. 21 b. 15120 c. 30 d. 6!*5! e. 6* (7!/2!)
Answer is a i.e. 21.
Two different answer explanations are given for above two qs and i think answer explanation should be same as well as the answer.
Can you guys pls help me understanding the explanation and the correct answer.
Hi, please note that the first one is a permutation question while the second one is combination.
1. 6 girls can be arranged in 6! Ways, now we have total 7 slots for 5 boys so they can be arranged in 7P5 ways.
2. Applying the same concept here:6 positive signs that can be arranged in only One way, now we have 7 slots for 5 negative signs...applying the combination formula..its 7C5 =21.
Note that order in which boys or girls sit is important. Hence, Permutation G1 to G6 can be arranged in 6! ways. Seven slots can be alloted to 5 boys in 7P5 ways. The answer is 6! x 7P5
7 gaps are available and we have 5 negative signs. All positive/ negative signs are the same and order of arrangement is not important. Hence, combinations, 7C5 = 42/2 = 21 ways
Hi Guys,
I saw two similar questions have different explanation and two different answers.
Q1. How many ways 5 boys and 6 girlsbe arranged in a row so that no two boys are together. Below are the answer choices: a. 7 * 6! b. 6!*5!*2 c. 6!*5! P 5
d. 7 * 5! P 5 e.6 * 6! P 5 Answer is a.
Q2. How many ways can 6 positive and 5 negative sings be arranged in a row so that no two negative sings are together. Below are the answer choices:
a. 21 b. 15120 c. 30 d. 6!*5! e. 6* (7!/2!)
Answer is a i.e. 21.
Two different answer explanations are given for above two qs and i think answer explanation should be same as well as the answer.
Can you guys pls help me understanding the explanation and the correct answer.
A challenging probability question which came to my mind...
Q) If a man climbs a staircase having 12 steps by jumping one step, two steps or three steps at a time in any order. What is the probability that he took at least two three step jumps?
The first question talks on PEOPLE (who look different) 😁 and hence PERMUTATIONS to be used :)
Ans: 6! X 7P5.
The second one talks on SIGNS (which look similar) and hence COMBINATIONS to be used :)
Ans: 6C6 X 7C5 = 21
Hi Guys,
I saw two similar questions have different explanation and two different answers.
Q1. How many ways 5 boys and 6 girlsbe arranged in a row so that no two boys are together. Below are the answer choices: a. 7 * 6! b. 6!*5!*2 c. 6!*5! P 5
d. 7 * 5! P 5 e.6 * 6! P 5 Answer is a.
Q2. How many ways can 6 positive and 5 negative sings be arranged in a row so that no two negative sings are together. Below are the answer choices:
a. 21 b. 15120 c. 30 d. 6!*5! e. 6* (7!/2!)
Answer is a i.e. 21.
Two different answer explanations are given for above two qs and i think answer explanation should be same as well as the answer.
Can you guys pls help me understanding the explanation and the correct answer.
Kindly share the answers. I shall share the solutions then :)
I have posted these questions here because I do not have the solutions or the answers. If I had the answers, I would have definitely posted them at the end of the post. Will appreciate if you could share the solutions. 😃
Guys suggest me some books on quant as i have only OG's and CAT books are difficult as per gmat standard is concern...So which book to buy... Where do you get these questions so that i can use mine 2(brain)...this is medium cat level stuff what i believe..does GMAT standard require this? Pls reply..
Guys suggest me some books on quant as i have only OG's and CAT books are difficult as per gmat standard is concern...So which book to buy... Where do you get these questions so that i can use mine 2(brain)...this is medium cat level stuff what i believe..does GMAT standard require this? Pls reply..
OGs are sufficient practice material for GMAT quant. And if you think you need more practice then there are certain documents I came across while my preparation 1000DS and 1000 PS. You can find them online. And if you are thorough with CAT stuff and the quant level used there then GMAT quant should be a cake walk for you.
OGs are sufficient practice material for GMAT quant. And if you think you need more practice then there are certain documents I came across while my preparation 1000DS and 1000 PS. You can find them online. And if you are thorough with CAT stuff and the quant level used there then GMAT quant should be a cake walk for you.
Good Luck!
No iam not thorough with CAT level quant but rather i don't want to do it as it doesn't required by GMAC standard GMAT. So if you can give me 1000PS/DS i will be delighted.b/w when you are planning to give GMAT.
Note:- pls post the books from which you have posted these q's on this forum..
)
and hence COMBINATIONS to be used :)