(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

What are the last two digits of 16^198

2. Relevant equations

3. The attempt at a solution

I begin by looking for a pattern.

16^2 = 256

16^4 = ...36

16^6 = ...16

16^8 = ...96

16^10 = ...56

so i see that the pattern repeats itself every 4 times. Then, i grouped the power as follows,

(2,4,6,8) , (10,12,14,16) , (18,20,22,24) , ... , (194,196,198,200)

The last number of each group has formula of 8n and that's how i got the last group.

198 is third in the group which corresponds to the number having 16 as its last two digits.

But i think i went wrong somewhere because the answer given is 96. Am i totally off track?

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# Homework Help: Last two digits of 16^198

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