Refer to
https://www.beatthegmat.com/difficult-ma ... -t795.html
digit numbers
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Source: Beat The GMAT — Problem Solving |
Here u go
0 1 2 3 4 5
x x x
5 5 4 = 100
100 place digit can be selected in 5 ways [12345]
10 place digit can be selected in 5 ways 0-6 except one used just before
unit place digit can be selected in 4 ways 0-6 except one used at 10 and 100 place
total = 5 5 4 = 100
Odd
unit place 3 [135]
100 place in 4 ways [12345 - 1 digit used just before]
10 place digit in 4 ways
total = 3 4 4 = 48
even = 100 - 52
0 1 2 3 4 5
x x x
5 5 4 = 100
100 place digit can be selected in 5 ways [12345]
10 place digit can be selected in 5 ways 0-6 except one used just before
unit place digit can be selected in 4 ways 0-6 except one used at 10 and 100 place
total = 5 5 4 = 100
Odd
unit place 3 [135]
100 place in 4 ways [12345 - 1 digit used just before]
10 place digit in 4 ways
total = 3 4 4 = 48
even = 100 - 52
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scoobydooby
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i have a doubt:
i worked the question similar way, got 100 total 3 digit numbers, i worked out the number of even numbers first, i got 48 (4*4*3) and the balance 52 gave me the number of odd numbers. did i go wrong somehere?
i worked the question similar way, got 100 total 3 digit numbers, i worked out the number of even numbers first, i got 48 (4*4*3) and the balance 52 gave me the number of odd numbers. did i go wrong somehere?
