What is the remainder when the square of n is divided by 5 1. n divided by 5 leaves a remainder 3

Answer

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Hint: Here for answering these types of questions we need to observe the ones digit for general exact divisible numbers by 5 and we will add 3 to them and verify the options. Since we know that \[number=dividend\times divisor+remainder\]

Complete step-by-step answer:

The numbers which are exactly divisible by $5$ are $0, 5, 10, 15, 20, 25………….and\ so\ on$.If we observe the above pattern that any number having $0$ or $5$ in the ones digit is exactly divisible by $5$.So if we have a number $r$ as remainder then we are sure that it will be less than $5$ and now we can say that the number which leaves r as remainder will have $r+5$ or $r+0$ as the ones digit.Here, in the question it is given that the number N when divided by 5 leaves a remainder 3.So here we will have $3+5$ or $3+0$ as the ones digit for N.Hence here we will have 3 or 8 as the ones digit for N.

So, the correct answer is “Option B”.

Note: For answering questions of these type it would be efficient if we remember the simply rules to find the perfect dividend of a divisor they are

(i) For 2 it should be even, that is it has 0, 2, 4, 6, 8 (any one) as the ones digit.(ii) For 3 the sum of all digits of the number should be multiple of 3.(iii) For 5 it should have 0, 5 as one digit.(iv) For 6 it should be divisible by both 2 and 3.(v) For 9 the sum of all digits of the number should be multiple of 9.(vi) For 10 it should have 0 as one digit.Similarly if observed we can get for all numbers.

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