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Hi all,
I found this problem in a personality development test.
A train which is 100m long starts running at the speed of 70km/hr. A man also starts running at 10 kms/hr. In how much time does the train cross the man.
I got an approximate answer of 6 seconds when i tried to compute it by taking when the train covers 100 m then the man would have run for 15 m. Then when the train runs for 15 m, the man would have run 1.67 m and so on till I neared zero and got the answer as 6 seconds.
Could you tell me if there is a better way to do it?
Regards
Aishwarya
Hi ,
You have taken x + y + z = 10. The total is not ten. The number of animals of each kind not being less than 10. So we need to assume that there are 10 animals of each kind.
Regards
Aishwarya
Hello everybody,
I am back with a new problem in P&C
Q - There are stalls for 10 animals in a ship. In how ways can the shipload be made if there cows, calves and horses, and there are not less than 10 animals of each kind?
Regards
Aishwarya
Yes I think we sould be concluding that the answer in the source is incorrect. It was good cracking it. Thanks.
I am sorry. It shoud be 7!*5!*3 and not 7!*5!*2. It was a typo. Its the simplification of 4*3 * 7 * 6*5 * 6!.
Hi,
Thanks for your help here.
The answer in the source is 4!*5!*7!. However, if we sum up the possibilities as we listed above this is what we get - 4!*6!*5*3+7!*5!*2.
Regards
Aishwarya
A family comprised of an old man, 6 adults and 4 children is to be seated in a row with the condition that the children would occupy both the ends and nver occupy either side of the old man. How many sitting aarangements are possible?
Hi,
Yes, I got the same answer 4*3 * 7 * 6*5 * 6!
Going by the logic that 2 children occupy the ends - 4*3,
then the selection of 2 adults next to the children - 6*5
The Old man has 7 options now to seat himself - *7
The balance 6 people ( 2 Children and 4 Adults) - 6!
But there is an anomaly in thinking like this. Since, in the 7 positions that the old man may occupy they are positions where he may have a child on his right or left or both which must be ruled out.
However, the source from where I picked this question, the answer is 4!*5*7!
Could you help me with the 2nd question alone?
Thanks a lot for the help!!!
Thank you very much to both of you. In the 1st question you had answered it as 2^8 ways. If going by the same logic then, the answer to this question - In how many ways can 9 letters be posted in 4 letter boxes - will be 4^9.
Could you please clarify if I am correct?
Also, I have questions.
1. A computer has 5 terminals and each terminal is capable of four distinct positions including the positions of rest what is the total number of signals that can be made?
2. A family comprised of an old man, 6 adults and 4 children is to be seated in a row with the condition that the children would occupy both the ends and nver occupy either side of the old man. How many sitting aarangements are possible?
3. A party of 6 is to be formed from 10 men and 7 women so as to include 3 men and 3 women. In how many ways can it be formed if 2 particular women refuse to join it?
Regards
Aishwarya
Hi I have couple doubts in the above topic.
1. In a crossword puzzle 20 words are to be guessed of which 8 words have each an alternative solution. What is the number of possible solution?
2. Find the number of ways in which an arrangement of 4 letters can be made from the word "Mathematics"
Thank You
Regards
Aishwarya
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