The easy way to solve such questions is to divide the numbers individually by 8 and then multiply the remainders. Confirm whether the product of the remainders can be divided by 8 again. If yes, then divide and find the remainder and that will be your answer. If not, then the product of the remainders is your answer.
Here are a few examples to show this.
Find the remainder of 15*9/4. 15/4 gives a remainder of 3 and 9/4 gives a remainder of 1. Hence, the total remainder is the product of the remainders=3 which cannot be further divided BY 4. Let us confirm this the long way. 15*9=135. Divide 135 by 4 and you get a quotient of 33 and a remainder of 3.
Similarly, try 21*9/7. 21/7 gives a remainder os 0 and 9/7 gives a remainder of 2. Hence, 0*2=0 is the total remainder. You can try this the long way.
Now, coming to the question at hand 47/8 gives a reminder of 7 and 49/8 gives a remainder of 1. 7*1=7 is the total remainder and thus, the answer is e.
Hope this helps! Let me know in case of any further questions.
What is the remainder when (47)(49) is divided by 8?
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