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Numerical Ability
Permutation and Combination
How many numbers greater than 5000 can be formed with four of the digits 3, 4, 5, 6, 7 where no digit can be repeated.
Read Solution (Total 4)
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- 72
3*4*3*2=72 - 13 years agoHelpfull: Yes(19) No(5)
- for 4 digit number greater than 5000- fix first digit as 5(5_ _ _)now to fill the 2nd place we have 4 optins for filling 3rd place 3 options and for filling 2nd place 2 options. so total options 4*3*2=24. similarly fix digit 6 and 7 at thousand place to get 24 nd 24 options respectively. to form 5 digit number (_ _ _ _ _) we have 5 options for 1st pace, 4 options for 2nd...and so on giving 5*4*3*2*1=120 options. So total of numbers>5000= 120+24+24+24=192.
- 13 years agoHelpfull: Yes(9) No(11)
- in addition we have to choose a number greater than 5 at the very left digit place so number of digits are 3 so we multiply 24 by 3 ....therefore 72 is the answer ..i think.
- 13 years agoHelpfull: Yes(5) No(5)
- we can form 24 4-digit numbers greater than 5000 as we have to choose 3 numbers from 3,4,6,7 so we use 4C3 and to arrange them 3! so we multiply 4C3 with 3! to get the answer.
- 13 years agoHelpfull: Yes(1) No(5)
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