If n is any integer, in the simplest expression how would you write an odd multiple of 5?

Question

The exact question is write the simplest expression you can to match each description using n. Let n be any integer. -an odd multiple of 5___ I've tried lots of things and they've all been wrong, it doesn't allow multiply or divide.

Answer 1

I am not sure what does "it doesn't allow multiply or divide" mean, will this work: 10 N + 5 ?

A general formula will be as: 5 * (2*N+1), where N belongs to Z.

UPDATE.

The real question here is how to figured this out by yourself? What kind of logic will help? This is because a really smart guy doesn't care about a single answer, he wants to know an approach, he wants to own a tool, right? This way he owns the World (at least some part of it).

1) write down what you want to get.

5 15 25 35 45

2) Stare at this sequence and think, get coffee if you need to.

3) You know this is an odd multiple of 5, but it is STILL the odd multiple, so a general rule for ODD has to be involved in some way. At least it worth to try, so write this down together:

5 15 25 35 45 -->>> ????

1 3 5 7 9. -->>> ( 2 * N +1)

4) Stare again. As you can see, the only difference is that values at the upper sequence are 5 times more than at the lower one.

Answer: ( 2 * N +1) * 5 = 10 * N + 5

Done!!!