Problema Solution

You and your brother both work the​ 4:00 P.M. to midnight shift. You have every fourth night off. Your brother has every sixth night off. Both of you were off on November 1. Your brother would like to see a movie with you. When will the two of you have the same night off​ again?

Answer provided by our tutors

We need to find the least common multiple for 4 and 6:

LCM(4, 6) = 12

This means that the 12th day after November 1 will be their night off together, that is on 1 + 12 = 13 of November.

Indeed:

You: 

1 November - night off

5 November - night off

9 November - night off

13 November - night off

Your brother:

1 November - night off

7 November - night off

13 November - night off