cmccray26 wrote:
How would you know to look for cyclical pattern here?
And can someone further explain?
First Concept: any number when divided by 10 gives the last digit remainder. Check with numbers.
Second concept: In order to find the last digit we need to find a patter, in GMAT you can't calculate 7^442.
Now, how to find the cyclicity of numbers? try to understand the concepts:
https://gmatclub.com/forum/cyclicity-92381.html#p711962Next, For 7 you can check it yourself-
7^1, last digit 7
7^2, last digit 9
7^3, last digit 3
7^4, last digit 1
7^5, last digit 7...
So, for a number in the format 7^(4n+
2) will have last digit 9.
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