GMAT
Numerical Ability
Number System
Q. How many odd numbers less than 1000 can be formed using the digits 0, 2, 5, 7? (repetition of digits is allowed ?
Read Solution (Total 11)
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- odd numbers less than 1000
3 digit no.=3*4*2=24
2 digit no.=2*3=6
1 digit no.=2
so total odd no. less than 1000 =24+6+2=32
ans 32 - 11 years agoHelpfull: Yes(10) No(2)
- i think 14
- 11 years agoHelpfull: Yes(2) No(6)
- 3digit no.- 3*4*2=24
2digit no.- 3*2=6
1digit no.- 2(odd, 5 nd 7)
Total= 24+6+2=32 - 11 years agoHelpfull: Yes(1) No(1)
- 3*4*2=24
any digit except 0 can come at first place so 3 ways
then any digit at tens place so 4 ways
either 0 or 2 at units place so 2 ways
3*2*4=24 - 11 years agoHelpfull: Yes(0) No(3)
- 32
For three digit odd numbers _ _ _ the first place cannot be filled by 0. other three can fill. Second place can be filled by all 4. Third place cannot be filled by either 2 or 0. So, 3*4*2=24.
For two digit odd numbers _ _. First place cannot be filled by 0. Other three can fill. Second place can be filled either by 5 or 7. So 3*2=6.
For single digit odd numbers it can either be 5 or 7. so 2.
24+6+2=32 - 10 years agoHelpfull: Yes(0) No(1)
- ans=48
3 digit=3
2nd digit=4
1st digit=4
so total odd no=4*4*3=48
- 10 years agoHelpfull: Yes(0) No(2)
- very easy, 1c1*4c1*4c1*2c1 =32.
1c1 bwcause anything without 0 will make it more than 1000 & 2c1 because with only 5 or 7 the number will be odd. - 10 years agoHelpfull: Yes(0) No(0)
- 32 :)
confirm ! - 10 years agoHelpfull: Yes(0) No(0)
- three digit number:
last no must be 5,7 only 2 option is possible.
way=4*4*2=32. - 10 years agoHelpfull: Yes(0) No(0)
- Places: 4th place 3rd place 2nd place unit pace
nos can be placed: 0 0,2,5,7 0,2,5,7 5,7
possibilities: 1 4P1=4 4P1=4 2P1=2
Total no of odd nos = 1+4+4+2 = 11
- 10 years agoHelpfull: Yes(0) No(0)
- Its a based on P & C, 4 boxes are there.
1.first box can be filled in 1 ways ( 0 )
2. Second box can be in 4 ways
3. Third box can be in 4 ways.
4.Fourth box can be in 2 ways (5 & 7)
Thus total permutation = 1*4*4*2
= 32 - 7 years agoHelpfull: Yes(0) No(0)
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