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If ^npr=720 and ^nCr=120 find r...

If `^np_r=720` and `^nC_r=120` find r

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A N EXCEL PUBLICATION-PERMUTATIONS AND COMBINATIONS-QUESTION BANK
  1. Evaluate the following ^(n+1)Cn

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  2. If ^nC10=^nC12 find ^23Cn

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  3. If ^npr=720 and ^nCr=120 find r

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  4. It was found at a certain dinner meeting that after every member had s...

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  5. In how many ways a committee of 5 members can be selected from 6 men a...

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  6. If m parallel lines in plane are intersected by a family of n parallel...

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  7. In how many ways can a cricket team of 11 of players be selected from ...

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  8. In how many ways can a cricket team of eleven be chosen out of a batch...

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  9. In how many ways can a cricket team of eleven be chosen out of a batch...

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  10. A question paper has two parts, part A and part B, each containing 10 ...

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  11. A committee of 6 is to be formed from 6 men and 4 women. In how many w...

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  12. A committee of 6 is to be formed from 6 men and 4 women. In how many w...

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  13. If ^nC8=^nC2find ^nC2

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  14. Determine n if ^(2n)C3:^nC2=12:1

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  15. Determine n if ^(2n)C3:^nC3=11:1

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  16. How many chords can be drawn through 21 points on a circle?

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  17. In how many ways can a team of 3 boys and 3 girls be selected from 5 b...

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  18. Find the number of ways of selecting 9 balls from 6 red balls, 5 white...

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  19. Determine the number of 5 card combinations out of a deck of 52 cards ...

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  20. In how many ways can one select a cricket team of eleven from 17 playe...

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