three-digit number n

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three-digit number n

by papgust » Fri Apr 09, 2010 5:07 am
Couldn't find this question in this forum.

Is the three-digit number n less than 550?

1) The product of the digits in n is 30
2) The sum of digits in n is 10

OA: C


I selected E. Somehow, i don't seem to get the logic of why the combined statement is sufficient. I guess i'm missing some concept.
Source: — Data Sufficiency |

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by dxgamez » Fri Apr 09, 2010 6:23 am
1. 30 - 2 x 3 x 5 or 6 x 5 x 1

Thus insufficient

2. Can be 235 or 640 or any number, so insufficient.

When we combined I saw that for product of digits to be 30, it would have to be 2 x 3 x 5. This gives us a max no of 532.

Thus sufficient. I hope I am correct in my thinking.

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by PeterFaulkner » Fri Apr 09, 2010 9:43 am
Is the three-digit number n less than 550?

Statement 1 is not sufficient because N can be:

561 obviously greater than 550
or
235 obviously less than 550


Statement 2 is not sufficient because it can be

109 obviously less than 550
or
901 obviously greater than 550

Together
N can be 235 or 532 both of which is less than 550

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by papgust » Fri Apr 09, 2010 7:20 pm
Thanks guys. I understand now.