3^2000 unit number =a

Question

0

667

1

+22

3^2000 unit number =a

x=3^36 9×'s unit number =b

What is a+b

sangyun Jan 12, 2015

+33661

+10

Best Answer

3ⁿ ends with a 1 in the units place whenever n is a multiple of 4, so both 3²⁰⁰⁰ and 3³⁶ end with a 1. So a = 1 and b = 9, hence a + b = 10

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Alan Jan 12, 2015

Alan · Answer 1 · 2015-01-12T10:37:38

3ⁿ ends with a 1 in the units place whenever n is a multiple of 4, so both 3²⁰⁰⁰ and 3³⁶ end with a 1. So a = 1 and b = 9, hence a + b = 10

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