# Counting numbers in a range which are divisible by $4$ or $13$

When you pick an integer from $1$ to $50$, how many cases are there that you pick a multiple of $4$ or $13$?

I thought maybe that if I counted by $4$: ($4+4 = 8$, $8+4=12$, etc) would will work, and I tried doing to same with $13$, but it didn't work. What am I doing wrong?

• $12*4=48$, so $12$ numbers are multiple of $4$ and $13*4=52>50$ so $3$ numbers multiple of $13$ – Vikram Mar 2 '15 at 3:35