Tbe remainder when n is divided by 2 is 1. What is the

Question

Tbe remainder when n is divided by 2 is 1. What is the remainder when 3n is divided by 8?

Not sure how to tackle these???

Fig · Answer

When n divided by 2, the remainer is 1. It's the definition of an odd number

... So, n = 2*k+1. What is the remainer of 3*n divided by 8?..... Pick odd integers (to know the behaviour)

o If n=1, then 3n = 3*1 = 3 = 8*0 + 3 => the remainer = 3 o If n=3, then 3n = 3*3 = 9 = 8*1 + 1 => the remainer = 1 o If n=5, then 3n = 3*5 = 15 = 8*1 + 7 => the remainer = 7 o If n=7, then 3n = 3*7 = 21 = 8*2 + 5 => the remainer = 5 o If n=9, then 3n = 3*9 = 27 = 8*3 + 3 => the remainer = 3 (A complete cycle) After, it depends on the rest of the question

gmat_enthus · Answer

basically its given that n is odd. n = 2k+1

now choose some consecutive odd numbers and see what is their remainder with 8. Its a cycle of 4.

cucrose · Answer

just so Im clear, its the remainder that determines if its an odd or even? If its odd remainder, you substitute odd numbers in and even numbers for an even remainder?

maxpowers · Answer

The reason behind it in this particular question is that an odd number does not have 2 as a factor by definition. Since n is not divisible by 2 we know its an odd number. 

If you had a situation with something other than 2, you can't say an odd remainder means you try odd numbers and an even remainder you try even numbers. Look at some examples.

If N=10 and its divided by 3, you get a remainder of 1. This is a case with an odd remainder and N is even.

Tbe remainder when n is divided by 2 is 1. What is the

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