Problema Solution

Beginning with 2, the digits in the ones place of even numbers are 2,4, 6, 8, 10, etc. Which digit is in the ones place of the 357th number?

Answer provided by our tutors

The digits in the ones place of even numbers are: 

2, 4, 6, 8, 0, 2, 4, 6, 8, 0,....

We notice that the following 5 digits repeat: 2,4,6,8,0

1st even number ends on: 2

2nd even number ends on: 4

3rd even number ends on: 6

4th even number ends on: 8

5th even number ends on: 0

6th even number ends on: 2

.....

We need to find the reminder when 357 is divided by 5.

For the 357th even number we have:

357 = 5*71 + 2

Meaning the ones place will be '4'.

Indeed the 357 even number is: 357*2 = 714