The sum looks as follows:
LMN
NOP
QRS
Since every digit must be used exactly once, the sum will be MINIMIZED if the blue digits are AS SMALL AS POSSIBLE and the red digits are AS BIG AS POSSIBLE, as in the following case:
1M7
2O8
3R9
Thus, the remaining 3 digits must be 4, 5, and 6:
147
258
369
774
The correct answer is C.
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unit digit problem
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
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Student Review #3
Waouuh! I like it.
Thank you very much Mitch!
I will follow the same logic when I will encounter a similar case.
Marc.
Thank you very much Mitch!
I will follow the same logic when I will encounter a similar case.
Marc.
The key takeaway here is the idea: if we're going to minimize a sum, where will we have the most impact? Here it's the 100s places, so we want those to be the smallest, etc.














