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Re: What is the units digit of 16^4 × 27^3?
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22 Feb 2021, 08:18
Solution:
We can use cyclicity here.
6 has a cyclicity of 1 i.e when you multiply 6 "n" number of times, you always get units digit 6
7 has a cyclicty if 4 i.e. 7,72=49,73=343,74=2401
Thus, 7 has 4 different units digit when multiplied by itself.
164will also have a units digit of 6
273will have a units digit 3
Hence, 6*3=18
IMO D
Hope this helps