We know to find what is the remainder when \( 3^{24} \) is divided by 5Theory: Remainder of a number by 5 is same as the reminder of the unit's digit of the number by 5(
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How to find Remainders of Numbers by 5)
Using Above theory , Let's find the unit's digit of \(3^{24}\) first.
We can do this by finding the pattern / cycle of unit's digit of power of 3 and then generalizing it.
Unit's digit of \(3^1\) = 3
Unit's digit of \(3^2\) = 9
Unit's digit of \(3^3\) = 7
Unit's digit of \(3^4\) = 1
Unit's digit of \(3^5\) = 3
So, unit's digit of power of 3 repeats after every \(4^{th}\) number.
=> We need to divided 24 by 4 and check what is the remainder
=> 24 divided by 4 gives 0 remainder
=> 3^{24} will have the same unit's digit as \(3^{Cycle}\) = Units digit of \(3^{4}\) = 1
=> Remainder of \(3^{24}\) by 5 = Remainder of 1 by 5 = 1
So,
Answer will be BHope it helps!
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