In this question we just have to look at the units digit to find out the remainder.
3^(8n+3) will always result in an odd integer for any value of n
therefore units place of the integer will either 3 or 7
3^(8n+3) +2 = either 5 or 9
Therefore we can eliminate all the options but 0 and 4.
The units place of 3^(8n+3) will always be 7
Hence the answer is 4.
Whats the OA?
remainder
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parallel_chase
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sudhir3127
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My answer is 4. using Mod Arithemetic,,
3^(8n+3) + 2 % 5
(3^ 8n.27)+ 2%5
using remainder theorem
3^8n%5 ~ 1
27%5~ 2
2%5~ 2
1*2 + 2 ~ 4
hence the answer.
3^(8n+3) + 2 % 5
(3^ 8n.27)+ 2%5
using remainder theorem
3^8n%5 ~ 1
27%5~ 2
2%5~ 2
1*2 + 2 ~ 4
hence the answer.
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sudhir3127
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vishubn
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Ya my take on the is also 4
...
the power is the multiple of 8 and to which 3 is added
so it is in the range 11,19,27,......
3 power of any of the number 11,19,27 will always give me the unit digit has 7
for the fact series of number 3 raised to somethign follows 3,9,7,1,3,9,7,1.....
so so the unit digits we constantly get here is ! the number 9
so the remainder is 4
vishu
...
the power is the multiple of 8 and to which 3 is added
so it is in the range 11,19,27,......
3 power of any of the number 11,19,27 will always give me the unit digit has 7
for the fact series of number 3 raised to somethign follows 3,9,7,1,3,9,7,1.....
so so the unit digits we constantly get here is ! the number 9
so the remainder is 4
vishu
