Question

When N divided by 5 leaves a remainder of 2, find the one's digit of N

Answer 1

Explanation:

One's digit of N can be 2 or 7.

Answer 2

Explanation:

If the number ends in 0 or 5 those are the only two results that 5 will divide into a number evenly.

For example 105/5 = 21

And example 1020/5 = 204

So if you want a remainder of 2, there are 2 ways to get it.

1) If the number ends in a two, you will get a remainder of 2. That's because 0 + 2 will give 2.

For example 252 / 5 = 50 with a remainder of 2

2) The other way is if the end number is 7.

3347 / 5 = 669 with a remainder of 2.

The reason this works is if you subtract 2 from the number given then the units digit will be either 0 or 5. Those two endings result in even division.