Campus
Maths Puzzle
Numerical Ability
Permutation and Combination
in how many ways can 7 different objects can be divided among 3 person so that either one or two do not get any object
Read Solution (Total 5)
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- Ans. 28
7C2+7C1=28
7C2---> if one did not get any object
7C1---> if two of them did not get any objects. - 10 years agoHelpfull: Yes(1) No(1)
- Case 1: Two guys don't get anything. All items go to 1 person. Hence, 3 ways.
Case 2: 1 guy doesn't get anything. Division of 7 items among 2 guys. Lets say they are called A & B.
a) A gets 6. B gets 1. 7 ways.
b) A gets 5. B gets 2. 21 ways.
c) A gets 4. B gets 3. 35 ways.
d) A gets 3. B gets 4. 35 ways.
e) A gets 2. B gets 5. 21 ways.
f) A gets 1. B gets 6. 7 ways.
Total = 126 ways to divide 7 items between A & B.
Total number of ways for case 2 = 126*3 = 378 (Either A, or B, or C don't get anything).
Answer = Case 1 + Case 2 = 3 + 378 = 381 - 10 years agoHelpfull: Yes(0) No(2)
- Sorry i misRead The Questtion
- 10 years agoHelpfull: Yes(0) No(1)
- 7c3-(7c2+7c1)
35-28=7
so answer is 7 - 10 years agoHelpfull: Yes(0) No(1)
- IF TW OF THEM GET NOTHING=(7C0*7C0*7C7)*3!=6
IF ONE O THEM GET NOTHING =(7C1*7C0*7C6)*3!=294
TOTAL=300 - 6 years agoHelpfull: Yes(0) No(1)
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