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Find the number of ways in which 8 beads can be arranged to form a wristband.

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Important Questions on Permutation and Combination

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If f=13   24   36    47   55   61S6 then f-1 is
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Five persons A, B, C, D and E are seated in a circular arrangement. If each of them is given a hat of one of the three colours red, blue and green, then the number of ways of distributing the hats such that the persons seated in adjacent seats get different coloured hats is
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The number of ways, in which 5 girls and 7 boys can be seated at a round  table so that no two girls sit together is
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How many natural numbers n are there such that n!+10 is a perfect square ?
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The number of ways in which 6 men and 5 women can sit at a round table if no two women are to sit together is given by
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The total number of permutations of n(>1) different things taken not more than r at a time, when each thing may be repeated any number of times is
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The number of ways 5 boys and 5 girls can be seated at a round table, so no two boys are adjacent is _____
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The sum of the digits in the unit's place of all the 4 - digit numbers formed by using the numbers 3, 4, 5 and 6, without repetition is :
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Find the number of ways of preparing a chain with 6 different coloured beads.
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A round table conference is attended by 3 Indians, 3 Chinese, 3 Canadians and 2 Americans. Find the number of ways of arranging them at the round table so that the delegates belonging to same country sit together.
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The number of all 3-digits numbers abc (in base 10) for which 10 is
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20 persons are invited for a party. The number of ways in which they and the host can seated at a circular table, if two particular persons be seated on either side of the host is equal to
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The number of distinct primes dividing 12!+13!+14! Is
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Two girls and four boys are to be seated in a row in such a way that the girls do not sit together. In how many different ways can it be done?
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The largest non-negative integer k such that 24k divides 13! is
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The number of 6 digit number that can be formed using the digits 0, 1, 2, 5, 7 and 9 which are divisible by 11 and no digit is repeated is:
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The number of four-digit numbers strictly greater than 4321 that can be formed using the digit 0,1,2,3,4,5 (repetition of digits is allowed) is:
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The number of ways in which 5 boys and 3 girls can be seated on a round table if a particular boy B1 and a particular girl G1 never sit adjacent to each other, is:
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The number of ways that a circle can be made out of 6 black and 4 white men standing on a ring, so that all the white men come together is
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Six persons A, B, C, D, E and F are to be seated at a circular table facing towards the centre. Then the number of ways that can be done if A must have either E or F on his immediate right and E must have either F or D on his immediate right, is