The remainder when 4282024 is divided by 21 is .
Answer
1
Solution
428 = 21 20 + 8, so 4282024 = (21 20 + 8)2024 leaves the same remainder as 82024 (all other binomial terms contain 21).
Now 82 = 64 = 63 + 1 = 21 3 + 1
82024 = (82)1012 = (1 + 63)1012 = 1 + 63 ( )
Hence the remainder is 1.
Answer: 1